Support asynchronous logging (#38094)

Closes #38578

Closes #28851

Signed-off-by: Martin Bartoš <mabartos@redhat.com>

docs/documentation/release_notes/topics/26_3_0.adoc

@@ -4,4 +4,9 @@ Previously, usage of remote stores was discouraged and the experimental feature
 In this release, the experimental feature was removed and usage of remote stores was restricted.
 If you previously used the `cache-embedded-remote-store` feature, see the link:{upgradingguide_link}[{upgradingguide_name}] for migration steps.
 
+= Asynchronous logging
 
+All available log handlers now support asynchronous logging capabilities.
+Asynchronous logging might be useful for deployments requiring **high throughput** and **low latency** to move log operations in a separate thread.
+
+For more details, see the https://www.keycloak.org/server/logging[Logging guide].

docs/guides/server/logging.adoc

@@ -176,6 +176,57 @@ If you want to have JSON logs in *ECS* (Elastic Common Schema) format for the co
 {"@timestamp":"2025-02-03T14:53:22.539484211+01:00","event.sequence":9608,"log.logger":"io.quarkus","log.level":"INFO","message":"Keycloak 999.0.0-SNAPSHOT on JVM (powered by Quarkus 3.17.8) started in 4.615s. Listening on: http://0.0.0.0:8080","process.thread.name":"main","process.thread.id":1,"mdc":{},"ndc":"","host.hostname":"host-name","process.name":"/usr/lib/jvm/jdk-21.0.3+9/bin/java","process.pid":77561,"data_stream.type":"logs","ecs.version":"1.12.2","service.environment":"prod","service.name":"Keycloak","service.version":"999.0.0-SNAPSHOT"}
 ----
 
+=== Asynchronous logging
+{project_name} supports asynchronous logging, which might be useful for deployments requiring **high throughput** and **low latency**.
+Asynchronous logging uses a separate thread to take care of processing all log records.
+The logging handlers are invoked in exactly the same way as with synchronous logging, only done in separate threads.
+You can enable asynchronous logging for all {project_name} log handlers.
+A dedicated thread will be created for every log handler with enabled asynchronous logging.
+
+The underlying mechanism for asynchronous logging uses a queue for processing log records.
+Every new log record is added to the queue and then published to the particular log handler with enabled asynchronous logging.
+Every log handler has a different queue.
+
+If the queue is already full, it blocks the main thread and waits for free space in the queue.
+
+==== When to use asynchronous logging
+
+* You need **lower latencies** for incoming requests
+* You need **higher throughput**
+* You have **small worker thread pool** and want to offload logging to separate threads
+* You want to reduce the impact of **I/O-heavy log handlers**
+* You are logging to **remote destinations** (e.g., network syslog servers) and want to avoid blocking worker threads
+
+WARNING: Be aware that enabling asynchronous logging might bring some **additional memory overhead** due to the additional separate thread and the inner queue.
+In that case, it is not recommended to use it for resource-constrained environments.
+Additionally, unexpected server shutdowns create a risk of **losing log records**.
+
+==== Enable asynchronous logging
+You can enable asynchronous logging globally for all log handlers by using `log-async` property as follows:
+
+<@kc.start parameters="--log-async=true"/>
+
+Or you can enable the asynchronous logging for every specific handler by using properties in the format `log-<handler>-async` (where `<handler>` is a log handler).
+If the property for a specific handler is not set, the value from the parent `log-async` property is used.
+
+You can use these properties as follows:
+
+<@kc.start parameters="--log-console-async=true --log-file-async=true --log-syslog-async=true"/>
+
+* `log-console-async` - Console log handler
+* `log-file-async` - File log handler
+* `log-syslog-async` - Syslog log handler
+
+==== Change queue length
+You can change the size of the queue used for the asynchronous logging.
+The default size is **512** log records in the queue.
+
+You can change the queue length as follows:
+
+<@kc.start parameters="--log-console-async-queue-length=512 --log-file-async-queue-length=512 --log-syslog-async-queue-length=512"/>
+
+These properties are available only when asynchronous logging is enabled for these specific log handlers.
+
 == Console log handler
 The console log handler is enabled by default, providing unstructured log messages for the console.
 

quarkus/config-api/src/main/java/org/keycloak/config/LoggingOptions.java

@@ -65,6 +65,12 @@ public class LoggingOptions {
             .caseInsensitiveExpectedValues(true)
             .build();
 
+    public static final Option<Boolean> LOG_ASYNC = new OptionBuilder<>("log-async", Boolean.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(false)
+            .description("Indicates whether to log asynchronously to all handlers.")
+            .build();
+
     public enum Output {
         DEFAULT,
         JSON;
@@ -130,6 +136,19 @@ public class LoggingOptions {
             .hidden()
             .build();
 
+    // Console Async
+    public static final Option<Boolean> LOG_CONSOLE_ASYNC = new OptionBuilder<>("log-console-async", Boolean.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(false)
+            .description("Indicates whether to log asynchronously to console. If not set, value from the parent property '%s' is used.".formatted(LOG_ASYNC.getKey()))
+            .build();
+
+    public static final Option<Integer> LOG_CONSOLE_ASYNC_QUEUE_LENGTH = new OptionBuilder<>("log-console-async-queue-length", Integer.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(512)
+            .description("The queue length to use before flushing writing when logging to console.")
+            .build();
+
     // File
     public static final Option<Boolean> LOG_FILE_ENABLED = new OptionBuilder<>("log-file-enabled", Boolean.class)
             .category(OptionCategory.LOGGING)
@@ -175,6 +194,19 @@ public class LoggingOptions {
             .description("Set the log output to JSON or default (plain) unstructured logging.")
             .build();
 
+    // File async
+    public static final Option<Boolean> LOG_FILE_ASYNC = new OptionBuilder<>("log-file-async", Boolean.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(false)
+            .description("Indicates whether to log asynchronously to file log. If not set, value from the parent property '%s' is used.".formatted(LOG_ASYNC.getKey()))
+            .build();
+
+    public static final Option<Integer> LOG_FILE_ASYNC_QUEUE_LENGTH = new OptionBuilder<>("log-file-async-queue-length", Integer.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(512)
+            .description("The queue length to use before flushing writing when logging to file log.")
+            .build();
+
     // Syslog
     public static final Option<Boolean> LOG_SYSLOG_ENABLED = new OptionBuilder<>("log-syslog-enabled", Boolean.class)
             .category(OptionCategory.LOGGING)
@@ -247,4 +279,16 @@ public class LoggingOptions {
             .description("Set the Syslog output to JSON or default (plain) unstructured logging.")
             .build();
 
+    // Syslog async
+    public static final Option<Boolean> LOG_SYSLOG_ASYNC = new OptionBuilder<>("log-syslog-async", Boolean.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(false)
+            .description("Indicates whether to log asynchronously to Syslog. If not set, value from the parent property '%s' is used.".formatted(LOG_ASYNC.getKey()))
+            .build();
+
+    public static final Option<Integer> LOG_SYSLOG_ASYNC_QUEUE_LENGTH = new OptionBuilder<>("log-syslog-async-queue-length", Integer.class)
+            .category(OptionCategory.LOGGING)
+            .defaultValue(512)
+            .description("The queue length to use before flushing writing when logging to Syslog.")
+            .build();
 }

quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/cli/Picocli.java

@@ -26,6 +26,7 @@ import static org.keycloak.quarkus.runtime.Environment.isRebuilt;
 import static org.keycloak.quarkus.runtime.cli.OptionRenderer.decorateDuplicitOptionName;
 import static org.keycloak.quarkus.runtime.cli.command.AbstractStartCommand.OPTIMIZED_BUILD_OPTION_LONG;
 import static org.keycloak.quarkus.runtime.configuration.ConfigArgsConfigSource.parseConfigArgs;
+import static org.keycloak.quarkus.runtime.configuration.Configuration.isUserModifiable;
 import static org.keycloak.quarkus.runtime.configuration.MicroProfileConfigProvider.NS_KEYCLOAK_PREFIX;
 import static org.keycloak.quarkus.runtime.configuration.mappers.PropertyMappers.maskValue;
 import static picocli.CommandLine.Model.UsageMessageSpec.SECTION_KEY_COMMAND_LIST;
@@ -507,12 +508,6 @@ public class Picocli {
         mapper.getDeprecatedMetadata().ifPresent(metadata -> handleDeprecated(deprecatedInUse, mapper, configValueStr, metadata));
     }
 
-    private static boolean isUserModifiable(ConfigValue configValue) {
-        // This could check as low as SysPropConfigSource DEFAULT_ORDINAL, which is 400
-        // for now we won't validate these as it's not expected for the user to specify options via system properties
-        return configValue.getConfigSourceOrdinal() >= KeycloakPropertiesConfigSource.PROPERTIES_FILE_ORDINAL;
-    }
-
     private static void checkRuntimeSpiOptions(String key, final List<String> ignoredRunTime) {
         if (!key.startsWith(PropertyMappers.KC_SPI_PREFIX)) {
             return;

quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/configuration/Configuration.java

@@ -20,6 +20,7 @@ package org.keycloak.quarkus.runtime.configuration;
 import static org.keycloak.quarkus.runtime.cli.Picocli.ARG_PREFIX;
 
 import java.util.Map;
+import java.util.Objects;
 import java.util.Optional;
 import java.util.Properties;
 
@@ -28,6 +29,7 @@ import io.smallrye.config.ConfigValue;
 import io.smallrye.config.SmallRyeConfig;
 
 import org.keycloak.config.Option;
+import org.keycloak.quarkus.runtime.cli.Picocli;
 import org.keycloak.utils.StringUtil;
 
 import static org.keycloak.quarkus.runtime.configuration.MicroProfileConfigProvider.NS_KEYCLOAK_PREFIX;
@@ -51,6 +53,18 @@ public final class Configuration {
         return getOptionalBooleanValue(NS_KEYCLOAK_PREFIX + option.getKey()).orElse(false);
     }
 
+    public static boolean isUserModifiable(ConfigValue configValue) {
+        // This could check as low as SysPropConfigSource DEFAULT_ORDINAL, which is 400
+        // for now we won't validate these as it's not expected for the user to specify options via system properties
+        return configValue.getConfigSourceOrdinal() >= KeycloakPropertiesConfigSource.PROPERTIES_FILE_ORDINAL;
+    }
+
+    public static boolean isSet(Option<?> option) {
+        return Optional.ofNullable(getKcConfigValue(option.getKey()))
+                .filter(Configuration::isUserModifiable)
+                .isPresent();
+    }
+
     public static boolean isTrue(String propertyName) {
         return getOptionalBooleanValue(propertyName).orElse(false);
     }

quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/configuration/mappers/LoggingPropertyMappers.java

@@ -1,6 +1,10 @@
 package org.keycloak.quarkus.runtime.configuration.mappers;
 
 import static org.keycloak.config.LoggingOptions.DEFAULT_LOG_FORMAT;
+import static org.keycloak.config.LoggingOptions.LOG_CONSOLE_ENABLED;
+import static org.keycloak.config.LoggingOptions.LOG_FILE_ENABLED;
+import static org.keycloak.config.LoggingOptions.LOG_SYSLOG_ENABLED;
+import static org.keycloak.quarkus.runtime.configuration.Configuration.isSet;
 import static org.keycloak.quarkus.runtime.configuration.Configuration.isTrue;
 import static org.keycloak.quarkus.runtime.configuration.mappers.PropertyMapper.fromOption;
 
@@ -40,6 +44,8 @@ public final class LoggingPropertyMappers {
                 fromOption(LoggingOptions.LOG)
                         .paramLabel("<handler>")
                         .build(),
+                fromOption(LoggingOptions.LOG_ASYNC)
+                        .build(),
                 // Console
                 fromOption(LoggingOptions.LOG_CONSOLE_OUTPUT)
                         .isEnabled(LoggingPropertyMappers::isConsoleEnabled, CONSOLE_ENABLED_MSG)
@@ -60,7 +66,7 @@ public final class LoggingPropertyMappers {
                         .transformer((value, ctx) -> addTracingInfo(value, LoggingOptions.LOG_CONSOLE_INCLUDE_TRACE))
                         .build(),
                 fromOption(LoggingOptions.LOG_CONSOLE_JSON_FORMAT)
-                        .isEnabled(LoggingPropertyMappers::isConsoleJsonEnabled, CONSOLE_ENABLED_MSG + " and output is set to 'json'")
+                        .isEnabled(LoggingPropertyMappers::isConsoleJsonEnabled, "%s and output is set to 'json'".formatted(CONSOLE_ENABLED_MSG))
                         .to("quarkus.log.console.json.log-format")
                         .paramLabel("format")
                         .build(),
@@ -76,6 +82,17 @@ public final class LoggingPropertyMappers {
                         .mapFrom(LoggingOptions.LOG, LoggingPropertyMappers.resolveLogHandler(LoggingOptions.DEFAULT_LOG_HANDLER.name()))
                         .to("quarkus.log.console.enable")
                         .build(),
+                // Console async
+                fromOption(LoggingOptions.LOG_CONSOLE_ASYNC)
+                        .mapFrom(LoggingOptions.LOG_ASYNC)
+                        .isEnabled(LoggingPropertyMappers::isConsoleEnabled, CONSOLE_ENABLED_MSG)
+                        .to("quarkus.log.console.async")
+                        .build(),
+                fromOption(LoggingOptions.LOG_CONSOLE_ASYNC_QUEUE_LENGTH)
+                        .isEnabled(LoggingPropertyMappers::isConsoleAsyncEnabled, "%s and asynchronous logging is enabled".formatted(CONSOLE_ENABLED_MSG))
+                        .to("quarkus.log.console.async.queue-length")
+                        .paramLabel("queue-length")
+                        .build(),
                 // File
                 fromOption(LoggingOptions.LOG_FILE_ENABLED)
                         .mapFrom(LoggingOptions.LOG, LoggingPropertyMappers.resolveLogHandler("file"))
@@ -114,6 +131,17 @@ public final class LoggingPropertyMappers {
                         .paramLabel("output")
                         .transformer(LoggingPropertyMappers::resolveLogOutput)
                         .build(),
+                // File async
+                fromOption(LoggingOptions.LOG_FILE_ASYNC)
+                        .mapFrom(LoggingOptions.LOG_ASYNC)
+                        .isEnabled(LoggingPropertyMappers::isFileEnabled, FILE_ENABLED_MSG)
+                        .to("quarkus.log.file.async")
+                        .build(),
+                fromOption(LoggingOptions.LOG_FILE_ASYNC_QUEUE_LENGTH)
+                        .isEnabled(LoggingPropertyMappers::isFileAsyncEnabled, "%s and asynchronous logging is enabled".formatted(FILE_ENABLED_MSG))
+                        .to("quarkus.log.file.async.queue-length")
+                        .paramLabel("queue-length")
+                        .build(),
                 // Log level
                 fromOption(LoggingOptions.LOG_LEVEL)
                         .to("quarkus.log.level")
@@ -187,33 +215,76 @@ public final class LoggingPropertyMappers {
                         .paramLabel("output")
                         .transformer(LoggingPropertyMappers::resolveLogOutput)
                         .build(),
+                // Syslog async
+                fromOption(LoggingOptions.LOG_SYSLOG_ASYNC)
+                        .mapFrom(LoggingOptions.LOG_ASYNC)
+                        .isEnabled(LoggingPropertyMappers::isSyslogEnabled, SYSLOG_ENABLED_MSG)
+                        .to("quarkus.log.syslog.async")
+                        .build(),
+                fromOption(LoggingOptions.LOG_SYSLOG_ASYNC_QUEUE_LENGTH)
+                        .isEnabled(LoggingPropertyMappers::isSyslogAsyncEnabled, "%s and asynchronous logging is enabled".formatted(SYSLOG_ENABLED_MSG))
+                        .to("quarkus.log.syslog.async.queue-length")
+                        .paramLabel("queue-length")
+                        .build(),
         };
 
         return defaultMappers;
     }
 
     public static boolean isConsoleEnabled() {
-        return isTrue(LoggingOptions.LOG_CONSOLE_ENABLED);
+        return isHandlerEnabled(LoggingOptions.Handler.console);
+    }
+
+    public static boolean isConsoleAsyncEnabled() {
+        return isHandlerAsyncEnabled(LoggingOptions.Handler.console);
     }
 
     public static boolean isConsoleJsonEnabled() {
-        return isConsoleEnabled() && Configuration.isTrue("quarkus.log.console.json.enabled");
+        return isConsoleEnabled() && isTrue("quarkus.log.console.json.enabled");
     }
 
     public static boolean isFileEnabled() {
-        return isTrue(LoggingOptions.LOG_FILE_ENABLED);
+        return isHandlerEnabled(LoggingOptions.Handler.file);
+    }
+
+    public static boolean isFileAsyncEnabled() {
+        return isHandlerAsyncEnabled(LoggingOptions.Handler.file);
     }
 
     public static boolean isFileJsonEnabled() {
-        return isFileEnabled() && Configuration.isTrue("quarkus.log.file.json.enabled");
+        return isFileEnabled() && isTrue("quarkus.log.file.json.enabled");
     }
 
     public static boolean isSyslogEnabled() {
-        return isTrue(LoggingOptions.LOG_SYSLOG_ENABLED);
+        return isHandlerEnabled(LoggingOptions.Handler.syslog);
+    }
+
+    public static boolean isSyslogAsyncEnabled() {
+        return isHandlerAsyncEnabled(LoggingOptions.Handler.syslog);
     }
 
     public static boolean isSyslogJsonEnabled() {
-        return isSyslogEnabled() && Configuration.isTrue("quarkus.log.syslog.json.enabled");
+        return isSyslogEnabled() && isTrue("quarkus.log.syslog.json.enabled");
+    }
+
+    private static boolean isHandlerEnabled(LoggingOptions.Handler handler) {
+        return switch (handler) {
+            case console -> isTrue(LOG_CONSOLE_ENABLED);
+            case file -> isTrue(LOG_FILE_ENABLED);
+            case syslog -> isTrue(LOG_SYSLOG_ENABLED);
+        };
+    }
+
+    private static boolean isHandlerAsyncEnabled(LoggingOptions.Handler handler) {
+        if (!isHandlerEnabled(handler)) {
+            return false;
+        }
+        var property = switch (handler) {
+            case console -> LoggingOptions.LOG_CONSOLE_ASYNC;
+            case file -> LoggingOptions.LOG_FILE_ASYNC;
+            case syslog -> LoggingOptions.LOG_SYSLOG_ASYNC;
+        };
+        return isSet(property) ? isTrue(property) : isTrue(LoggingOptions.LOG_ASYNC);
     }
 
     private static BiFunction<String, ConfigSourceInterceptorContext, String> resolveLogHandler(String handler) {
@@ -318,7 +389,7 @@ public final class LoggingPropertyMappers {
      */
     private static String addTracingInfo(String value, Option<Boolean> includeTraceOption) {
         var isTracingEnabled = TracingPropertyMappers.isTracingEnabled();
-        var includeTrace = Configuration.isTrue(includeTraceOption);
+        var includeTrace = isTrue(includeTraceOption);
         var isChangedLogFormat = !DEFAULT_LOG_FORMAT.equals(value);
 
         if (!isTracingEnabled || !includeTrace || isChangedLogFormat) {

quarkus/runtime/src/test/java/org/keycloak/quarkus/runtime/cli/PicocliTest.java

@@ -35,6 +35,7 @@ import java.util.stream.Stream;
 
 import org.junit.Ignore;
 import org.junit.Test;
+import org.keycloak.config.LoggingOptions;
 import org.keycloak.quarkus.runtime.Environment;
 import org.keycloak.quarkus.runtime.KeycloakMain;
 import org.keycloak.quarkus.runtime.configuration.ConfigArgsConfigSource;
@@ -314,7 +315,7 @@ public class PicocliTest extends AbstractConfigurationTest {
         NonRunningPicocli nonRunningPicocli = pseudoLaunch("start-dev", "--hostname=name", "--http-enabled=true");
         assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
         assertTrue(nonRunningPicocli.reaug);
-        assertEquals("dev", nonRunningPicocli.buildProps.getProperty(org.keycloak.common.util.Environment.PROFILE));;
+        assertEquals("dev", nonRunningPicocli.buildProps.getProperty(org.keycloak.common.util.Environment.PROFILE));
     }
 
     /**
@@ -393,7 +394,7 @@ public class PicocliTest extends AbstractConfigurationTest {
         NonRunningPicocli nonRunningPicocli = pseudoLaunch("export", "--db=dev-file", "--file=file");
         assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
         assertTrue(nonRunningPicocli.reaug);
-        assertEquals("prod", nonRunningPicocli.buildProps.getProperty(org.keycloak.common.util.Environment.PROFILE));;
+        assertEquals("prod", nonRunningPicocli.buildProps.getProperty(org.keycloak.common.util.Environment.PROFILE));
     }
 
     @Test
@@ -593,4 +594,92 @@ public class PicocliTest extends AbstractConfigurationTest {
         // second class kc form should not
         assertThat(nonRunningPicocli.getOutString(), not(containsString("kc.spi-events-listener-micrometer-user-event-metrics-enabled")));
     }
+
+    @Test
+    public void logAsyncDisabledParent() {
+        NonRunningPicocli nonRunningPicocli = pseudoLaunch("start-dev", "--log=file", "--log-console-async=true");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Disabled option: '--log-console-async'. Available only when Console log handler is activated"));
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--log=console", "--log-file-async=true");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Disabled option: '--log-file-async'. Available only when File log handler is activated"));
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--log=file", "--log-syslog-async=true");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Disabled option: '--log-syslog-async'. Available only when Syslog is activated"));
+    }
+
+    @Test
+    public void logAsyncGlobal() {
+        NonRunningPicocli nonRunningPicocli = pseudoLaunch("start-dev", "--log-async=true", "--log-console-async=false", "--log-console-async-queue-length=222");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Disabled option: '--log-console-async-queue-length'. Available only when Console log handler is activated"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--log-async=true", "--log-console-async-queue-length=222");
+        assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
+
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--log=console,file", "--log-async=true", "--log-console-async=false", "--log-console-async-queue-length=222");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Disabled option: '--log-console-async-queue-length'. Available only when Console log handler is activated"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--log=console,file", "--log-async=true", "--log-console-async=false", "--log-file-async-queue-length=222");
+        assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
+    }
+
+    @Test
+    public void logAsyncConsoleDisabledOptions() {
+        assertLogAsyncHandlerDisabledOptions(LoggingOptions.Handler.file, LoggingOptions.Handler.console, "Console log handler");
+    }
+
+    @Test
+    public void logAsyncFileDisabledOptions() {
+        assertLogAsyncHandlerDisabledOptions(LoggingOptions.Handler.console, LoggingOptions.Handler.file, "File log handler");
+    }
+
+    @Test
+    public void logAsyncSyslogDisabledOptions() {
+        assertLogAsyncHandlerDisabledOptions(LoggingOptions.Handler.console, LoggingOptions.Handler.syslog, "Syslog");
+    }
+
+    private void assertLogAsyncHandlerDisabledOptions(LoggingOptions.Handler logHandler, LoggingOptions.Handler logHandlerOptions, String logHandlerFullName) {
+        var logHandlerName = logHandler.toString();
+        var logHandlerOptionsName = logHandlerOptions.toString();
+
+        NonRunningPicocli nonRunningPicocli = pseudoLaunch("start-dev", "--log=%s".formatted(logHandlerName), "--log-%s-async-queue-length=invalid".formatted(logHandlerOptionsName));
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Invalid value for option '--log-%s-async-queue-length': 'invalid' is not an int".formatted(logHandlerOptionsName)));
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--log=%s".formatted(logHandlerName), "--log-%s-async-queue-length=768".formatted(logHandlerOptionsName));
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Disabled option: '--log-%s-async-queue-length'. Available only when %s is activated and asynchronous logging is enabled".formatted(logHandlerOptionsName, logHandlerFullName)));
+
+    }
+
+    @Test
+    public void logAsyncConsoleInvalidValues() {
+        assertLogAsyncHandlerInvalidValues(LoggingOptions.Handler.console);
+    }
+
+    @Test
+    public void logAsyncFileInvalidValues() {
+        assertLogAsyncHandlerInvalidValues(LoggingOptions.Handler.file);
+    }
+
+    @Test
+    public void logAsyncSyslogInvalidValues() {
+        assertLogAsyncHandlerInvalidValues(LoggingOptions.Handler.syslog);
+    }
+
+    protected void assertLogAsyncHandlerInvalidValues(LoggingOptions.Handler handler) {
+        var handlerName = handler.toString();
+
+        var nonRunningPicocli = pseudoLaunch("start-dev", "--log=%s".formatted(handlerName), "--log-%s-async=true".formatted(handlerName), "--log-%s-async-queue-length=invalid".formatted(handlerName));
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getErrString(), containsString("Invalid value for option '--log-%s-async-queue-length': 'invalid' is not an int".formatted(handlerName)));
+    }
 }

quarkus/runtime/src/test/java/org/keycloak/quarkus/runtime/configuration/test/LoggingConfigurationTest.java

@@ -31,6 +31,7 @@ import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
 import org.hamcrest.CoreMatchers;
+import org.jboss.logmanager.handlers.AsyncHandler;
 import org.junit.Test;
 import org.keycloak.config.LoggingOptions;
 import org.keycloak.quarkus.runtime.Environment;
@@ -319,4 +320,128 @@ public class LoggingConfigurationTest extends AbstractConfigurationTest {
         assertEquals("true", createConfig().getConfigValue("quarkus.log.console.enable").getValue());
     }
 
+    @Test
+    public void asyncDefaults() {
+        initConfig();
+
+        boolean defaultEnabled = false;
+        int defaultQueueLength = 512;
+
+        for (var handler : LoggingOptions.Handler.values()) {
+            assertAsyncProperties(handler, defaultEnabled, defaultQueueLength);
+        }
+    }
+
+    @Test
+    public void asyncProperties() {
+        boolean enabled = true;
+        int queueLength = 1024;
+
+        for (var handler : LoggingOptions.Handler.values()) {
+            setAsyncProperties(handler, enabled, queueLength);
+        }
+
+        initConfig();
+
+        for (var handler : LoggingOptions.Handler.values()) {
+            assertAsyncProperties(handler, enabled, queueLength);
+        }
+    }
+
+    @Test
+    public void asyncPropertiesIndividual() {
+        setAsyncProperties(LoggingOptions.Handler.console, true, 768);
+        setAsyncProperties(LoggingOptions.Handler.file, false, 1523);
+        setAsyncProperties(LoggingOptions.Handler.syslog, true, 888);
+
+        initConfig();
+
+        assertAsyncProperties(LoggingOptions.Handler.console, true, 768);
+        assertAsyncProperties(LoggingOptions.Handler.file, false, 1523);
+        assertAsyncProperties(LoggingOptions.Handler.syslog, true, 888);
+    }
+
+    @Test
+    public void asyncGlobalProperty() {
+        putEnvVar("KC_LOG_ASYNC", "true");
+
+        initConfig();
+
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.console, true);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.file, true);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.syslog, true);
+
+        onAfter();
+
+        putEnvVar("KC_LOG_ASYNC", "false");
+
+        initConfig();
+
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.console, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.file, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.syslog, false);
+    }
+
+    @Test
+    public void asyncGlobalPropertyOverrides() {
+        putEnvVar("KC_LOG_ASYNC", "true");
+        setAsyncLoggingEnabled(LoggingOptions.Handler.console, false);
+        initConfig();
+
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.console, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.file, true);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.syslog, true);
+
+        setAsyncLoggingEnabled(LoggingOptions.Handler.file, false);
+        initConfig();
+
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.console, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.file, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.syslog, true);
+
+        setAsyncLoggingEnabled(LoggingOptions.Handler.file, false);
+        initConfig();
+
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.console, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.file, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.syslog, true);
+
+        onAfter();
+
+        putEnvVar("KC_LOG_ASYNC", "false");
+        setAsyncLoggingEnabled(LoggingOptions.Handler.console, true);
+        initConfig();
+
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.console, true);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.file, false);
+        assertAsyncLoggingEnabled(LoggingOptions.Handler.syslog, false);
+
+    }
+
+    protected void setAsyncLoggingEnabled(LoggingOptions.Handler handler, Boolean enabled) {
+        // default values
+        setAsyncProperties(handler, enabled, 512);
+    }
+
+    protected void setAsyncProperties(LoggingOptions.Handler handler, Boolean enabled, Integer queueLength) {
+        var handlerName = handler.name();
+        putEnvVars(Map.of(
+                "KC_LOG_%s_ASYNC".formatted(handlerName), enabled.toString(),
+                "KC_LOG_%s_ASYNC_QUEUE_LENGTH".formatted(handlerName), queueLength.toString()
+                ));
+    }
+
+    protected void assertAsyncLoggingEnabled(LoggingOptions.Handler handler, Boolean expectedEnabled) {
+        var handlerName = handler.toString();
+        assertConfig("log-%s-async".formatted(handlerName), expectedEnabled.toString());
+        assertExternalConfig("quarkus.log.%s.async".formatted(handlerName), expectedEnabled.toString());
+    }
+
+    protected void assertAsyncProperties(LoggingOptions.Handler handler, Boolean enabled, Integer queueLength) {
+        assertAsyncLoggingEnabled(handler, enabled);
+
+        var handlerName = handler.toString();
+        assertConfig("log-%s-async-queue-length".formatted(handlerName), queueLength.toString());
+        assertExternalConfig("quarkus.log.%s.async.queue-length".formatted(handlerName), queueLength.toString());
+    }
 }

quarkus/tests/integration/src/test/java/org/keycloak/it/cli/dist/LoggingDistTest.java

@@ -31,6 +31,7 @@ import java.nio.charset.Charset;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 
+import org.hamcrest.CoreMatchers;
 import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.api.Test;
 import org.keycloak.config.LoggingOptions;
@@ -41,6 +42,7 @@ import org.keycloak.it.junit5.extension.RawDistOnly;
 import org.keycloak.it.utils.KeycloakDistribution;
 import org.keycloak.it.utils.RawDistRootPath;
 import org.keycloak.it.utils.RawKeycloakDistribution;
+import org.keycloak.quarkus.runtime.configuration.Configuration;
 import org.testcontainers.shaded.org.apache.commons.io.FileUtils;
 
 import io.quarkus.deployment.util.FileUtil;
@@ -258,6 +260,12 @@ public class LoggingDistTest {
         assertThat(data, containsString("@timestamp"));
     }
 
+    @Test
+    @Launch({"start-dev", "--log-async=true"})
+    void asyncLogging(CLIResult cliResult) {
+        cliResult.assertStartedDevMode();
+    }
+
     protected static String readDefaultFileLog(RawDistRootPath path) {
         Path logFilePath = Paths.get(path.getDistRootPath() + File.separator + LoggingOptions.DEFAULT_LOG_PATH);
         File logFile = new File(logFilePath.toString());

quarkus/tests/integration/src/test/java/org/keycloak/it/cli/dist/OptionsDistTest.java

@@ -20,8 +20,6 @@ package org.keycloak.it.cli.dist;
 import java.nio.file.Paths;
 
 import io.quarkus.test.junit.main.Launch;
-import io.quarkus.test.junit.main.LaunchResult;
-import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.MethodOrderer;
 import org.junit.jupiter.api.Order;
 import org.junit.jupiter.api.Test;
@@ -33,8 +31,6 @@ import org.keycloak.it.junit5.extension.RawDistOnly;
 import org.keycloak.it.junit5.extension.WithEnvVars;
 import org.keycloak.it.utils.KeycloakDistribution;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.keycloak.quarkus.runtime.cli.command.Main.CONFIG_FILE_LONG_NAME;
 
 @DistributionTest
@@ -45,33 +41,33 @@ public class OptionsDistTest {
     @Test
     @Order(1)
     @Launch({"build", "--db=invalid"})
-    public void failInvalidOptionValue(LaunchResult result) {
-        Assertions.assertTrue(result.getErrorOutput().contains("Invalid value for option '--db': invalid. Expected values are: dev-file, dev-mem, mariadb, mssql, mysql, oracle, postgres"));
+    public void failInvalidOptionValue(CLIResult result) {
+        result.assertError("Invalid value for option '--db': invalid. Expected values are: dev-file, dev-mem, mariadb, mssql, mysql, oracle, postgres");
     }
 
     @DryRun
     @Test
     @Order(2)
     @Launch({"start", "--db=dev-file", "--test=invalid"})
-    public void testServerDoesNotStartIfValidationFailDuringReAugStart(LaunchResult result) {
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Unknown option: '--test'")).count());
+    public void testServerDoesNotStartIfValidationFailDuringReAugStart(CLIResult result) {
+        result.assertError("Unknown option: '--test'");
     }
 
     @DryRun
     @Test
     @Order(3)
     @Launch({"start", "--db=dev-file", "--log=console", "--log-file-output=json", "--http-enabled=true", "--hostname-strict=false"})
-    public void testServerDoesNotStartIfDisabledFileLogOption(LaunchResult result) {
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Disabled option: '--log-file-output'. Available only when File log handler is activated")).count());
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Possible solutions: --log, --log-console-output, --log-console-level, --log-console-format, --log-console-color, --log-level")).count());
+    public void testServerDoesNotStartIfDisabledFileLogOption(CLIResult result) {
+        result.assertError("Disabled option: '--log-file-output'. Available only when File log handler is activated");
+        result.assertError("--log, --log-async, --log-console-output, --log-console-level, --log-console-format, --log-console-color, --log-console-async, --log-level, --log-level-<category>");
     }
 
     @DryRun
     @Test
     @Order(4)
     @Launch({"start", "--db=dev-file", "--log=file", "--log-file-output=json", "--http-enabled=true", "--hostname-strict=false"})
-    public void testServerStartIfEnabledFileLogOption(LaunchResult result) {
-        assertEquals(0, result.getErrorStream().stream().filter(s -> s.contains("Disabled option: '--log-file-output'. Available only when File log handler is activated")).count());
+    public void testServerStartIfEnabledFileLogOption(CLIResult result) {
+        result.assertNoError("Disabled option: '--log-file-output'. Available only when File log handler is activated");
     }
 
     @Test
@@ -105,42 +101,42 @@ public class OptionsDistTest {
     @Test
     @Order(7)
     @Launch({"start-dev", "--test=invalid"})
-    public void testServerDoesNotStartIfValidationFailDuringReAugStartDev(LaunchResult result) {
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Unknown option: '--test'")).count());
+    public void testServerDoesNotStartIfValidationFailDuringReAugStartDev(CLIResult result) {
+        result.assertError("Unknown option: '--test'");
     }
 
     @DryRun
     @Test
     @Order(8)
     @Launch({"start-dev", "--log=console", "--log-file-output=json"})
-    public void testServerDoesNotStartDevIfDisabledFileLogOption(LaunchResult result) {
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Disabled option: '--log-file-output'. Available only when File log handler is activated")).count());
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Possible solutions: --log, --log-console-output, --log-console-level, --log-console-format, --log-console-color, --log-level")).count());
+    public void testServerDoesNotStartDevIfDisabledFileLogOption(CLIResult result) {
+        result.assertError("Disabled option: '--log-file-output'. Available only when File log handler is activated");
+        result.assertError("Possible solutions: --log, --log-async, --log-console-output, --log-console-level, --log-console-format, --log-console-color, --log-console-async, --log-level, --log-level-<category>");
     }
 
     @DryRun
     @Test
     @Order(9)
     @Launch({"start-dev", "--log=file", "--log-file-output=json", "--log-console-color=true"})
-    public void testServerStartDevIfEnabledFileLogOption(LaunchResult result) {
-        assertEquals(0, result.getErrorStream().stream().filter(s -> s.contains("Disabled option: '--log-file-output'. Available only when File log handler is activated")).count());
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Disabled option: '--log-console-color'. Available only when Console log handler is activated")).count());
-        assertEquals(1, result.getErrorStream().stream().filter(s -> s.contains("Possible solutions: --log, --log-file, --log-file-level, --log-file-format, --log-file-json-format, --log-file-output, --log-level, --log-level")).count());
+    public void testServerStartDevIfEnabledFileLogOption(CLIResult result) {
+        result.assertNoError("Disabled option: '--log-file-output'. Available only when File log handler is activated");
+        result.assertError("Disabled option: '--log-console-color'. Available only when Console log handler is activated");
+        result.assertError("Possible solutions: --log, --log-async, --log-file, --log-file-level, --log-file-format, --log-file-json-format, --log-file-output, --log-file-async, --log-level, --log-level-<category>");
     }
 
     @DryRun
     @Test
     @Order(10)
     @Launch({"start-dev", "--cache-remote-host=localhost"})
-    public void testCacheRemoteHostWithoutMultiSite(LaunchResult result) {
-        assertErrorStreamContains(result, "cache-remote-host available only when feature 'multi-site' or 'clusterless' is set");
+    public void testCacheRemoteHostWithoutMultiSite(CLIResult result) {
+        result.assertError( "cache-remote-host available only when feature 'multi-site' or 'clusterless' is set");
     }
 
     @DryRun
     @Test
     @Order(11)
     @Launch({"start-dev", "--cache-remote-port=11222"})
-    public void testCacheRemotePortWithoutCacheRemoteHost(LaunchResult result) {
+    public void testCacheRemotePortWithoutCacheRemoteHost(CLIResult result) {
         assertDisabledDueToMissingRemoteHost(result, "--cache-remote-port");
     }
 
@@ -148,7 +144,7 @@ public class OptionsDistTest {
     @Test
     @Order(12)
     @Launch({"start-dev", "--cache-remote-username=user"})
-    public void testCacheRemoteUsernameWithoutCacheRemoteHost(LaunchResult result) {
+    public void testCacheRemoteUsernameWithoutCacheRemoteHost(CLIResult result) {
         assertDisabledDueToMissingRemoteHost(result, "--cache-remote-username");
     }
 
@@ -156,7 +152,7 @@ public class OptionsDistTest {
     @Test
     @Order(13)
     @Launch({"start-dev", "--cache-remote-password=pass"})
-    public void testCacheRemotePasswordWithoutCacheRemoteHost(LaunchResult result) {
+    public void testCacheRemotePasswordWithoutCacheRemoteHost(CLIResult result) {
         assertDisabledDueToMissingRemoteHost(result, "--cache-remote-password");
     }
 
@@ -164,7 +160,7 @@ public class OptionsDistTest {
     @Test
     @Order(14)
     @Launch({"start-dev", "--cache-remote-tls-enabled=false"})
-    public void testCacheRemoteTlsEnabledWithoutCacheRemoteHost(LaunchResult result) {
+    public void testCacheRemoteTlsEnabledWithoutCacheRemoteHost(CLIResult result) {
         assertDisabledDueToMissingRemoteHost(result, "--cache-remote-tls-enabled");
     }
 
@@ -172,31 +168,27 @@ public class OptionsDistTest {
     @Test
     @Order(15)
     @Launch({"start-dev", "--features=multi-site"})
-    public void testMultiSiteWithoutCacheRemoteHost(LaunchResult result) {
-        assertErrorStreamContains(result, "- cache-remote-host: Required when feature 'multi-site' or 'clusterless' is set.");
+    public void testMultiSiteWithoutCacheRemoteHost(CLIResult result) {
+        result.assertError("- cache-remote-host: Required when feature 'multi-site' or 'clusterless' is set.");
     }
 
     @DryRun
     @Test
     @Order(16)
     @Launch({"start-dev", "--features=multi-site", "--cache-remote-host=localhost", "--cache-remote-username=user"})
-    public void testCacheRemoteUsernameWithoutCacheRemotePassword(LaunchResult result) {
-        assertErrorStreamContains(result, "The option 'cache-remote-password' is required when 'cache-remote-username' is set.");
+    public void testCacheRemoteUsernameWithoutCacheRemotePassword(CLIResult result) {
+        result.assertError("The option 'cache-remote-password' is required when 'cache-remote-username' is set.");
     }
 
     @DryRun
     @Test
     @Order(17)
     @Launch({"start-dev", "--features=multi-site", "--cache-remote-host=localhost", "--cache-remote-password=secret"})
-    public void testCacheRemotePasswordWithoutCacheRemoteUsername(LaunchResult result) {
-        assertErrorStreamContains(result, "The option 'cache-remote-username' is required when 'cache-remote-password' is set.");
+    public void testCacheRemotePasswordWithoutCacheRemoteUsername(CLIResult result) {
+        result.assertError("The option 'cache-remote-username' is required when 'cache-remote-password' is set.");
     }
 
-    private static void assertDisabledDueToMissingRemoteHost(LaunchResult result, String option) {
-        assertErrorStreamContains(result, "Disabled option: '%s'. Available only when remote host is set".formatted(option));
-    }
-
-    private static void assertErrorStreamContains(LaunchResult result, String msg) {
-        assertTrue(result.getErrorStream().stream().anyMatch(s -> s.contains(msg)));
+    private static void assertDisabledDueToMissingRemoteHost(CLIResult result, String option) {
+        result.assertError("Disabled option: '%s'. Available only when remote host is set".formatted(option));
     }
 }

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testBootstrapAdminService.approved.txt

@@ -135,6 +135,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testBootstrapAdminUser.approved.txt

@@ -137,6 +137,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testExportHelp.approved.txt

@@ -130,6 +130,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testExportHelpAll.approved.txt

@@ -130,6 +130,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -158,6 +168,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -192,6 +210,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testImportHelp.approved.txt

@@ -130,6 +130,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testImportHelpAll.approved.txt

@@ -130,6 +130,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -158,6 +168,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -192,6 +210,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testStartDevHelp.approved.txt

@@ -285,6 +285,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testStartDevHelpAll.approved.txt

@@ -345,6 +345,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -373,6 +383,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -407,6 +425,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testStartHelp.approved.txt

@@ -317,6 +317,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testStartHelpAll.approved.txt

@@ -346,6 +346,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -374,6 +384,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -408,6 +426,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testStartOptimizedHelp.approved.txt

@@ -266,6 +266,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testStartOptimizedHelpAll.approved.txt

@@ -295,6 +295,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -323,6 +333,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -357,6 +375,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testUpdateCompatibilityCheckHelp.approved.txt

@@ -316,6 +316,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testUpdateCompatibilityCheckHelpAll.approved.txt

@@ -345,6 +345,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -373,6 +383,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -407,6 +425,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testUpdateCompatibilityMetadataHelp.approved.txt

@@ -314,6 +314,12 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.

quarkus/tests/integration/src/test/resources/org/keycloak/it/cli/dist/approvals/cli/help/HelpCommandDistTest.testUpdateCompatibilityMetadataHelpAll.approved.txt

@@ -343,6 +343,16 @@ Logging:
 
 --log <handler>      Enable one or more log handlers in a comma-separated list. Possible values
                        are: console, file, syslog. Default: console.
+--log-async <true|false>
+                     Indicates whether to log asynchronously to all handlers. Default: false.
+--log-console-async <true|false>
+                     Indicates whether to log asynchronously to console. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Console log handler is activated.
+--log-console-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to console.
+                       Default: 512. Available only when Console log handler is activated and
+                       asynchronous logging is enabled.
 --log-console-color <true|false>
                      Enable or disable colors when logging to console. Default: false. Available
                        only when Console log handler is activated.
@@ -371,6 +381,14 @@ Logging:
                        handler is activated.
 --log-file <file>    Set the log file path and filename. Default: data/log/keycloak.log. Available
                        only when File log handler is activated.
+--log-file-async <true|false>
+                     Indicates whether to log asynchronously to file log. If not set, value from
+                       the parent property 'log-async' is used. Default: false. Available only when
+                       File log handler is activated.
+--log-file-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to file log.
+                       Default: 512. Available only when File log handler is activated and
+                       asynchronous logging is enabled.
 --log-file-format <format>
                      Set a format specific to file log entries. Default: %d{yyyy-MM-dd HH:mm:ss,
                        SSS} %-5p [%c] (%t) %s%e%n. Available only when File log handler is
@@ -405,6 +423,14 @@ Logging:
 --log-syslog-app-name <name>
                      Set the app name used when formatting the message in RFC5424 format. Default:
                        keycloak. Available only when Syslog is activated.
+--log-syslog-async <true|false>
+                     Indicates whether to log asynchronously to Syslog. If not set, value from the
+                       parent property 'log-async' is used. Default: false. Available only when
+                       Syslog is activated.
+--log-syslog-async-queue-length <queue-length>
+                     The queue length to use before flushing writing when logging to Syslog.
+                       Default: 512. Available only when Syslog is activated and asynchronous
+                       logging is enabled.
 --log-syslog-endpoint <host:port>
                      Set the IP address and port of the Syslog server. Default: localhost:514.
                        Available only when Syslog is activated.