KAFKA-13610: Deprecate log.cleaner.enable configuration

core/src/main/scala/kafka/server/KafkaConfig.scala

@@ -339,7 +339,6 @@ class KafkaConfig private(doLog: Boolean, val props: util.Map[_, _])
   def logCleanerMaxCompactionLagMs = getLong(CleanerConfig.LOG_CLEANER_MAX_COMPACTION_LAG_MS_PROP)
   def logCleanerBackoffMs = getLong(CleanerConfig.LOG_CLEANER_BACKOFF_MS_PROP)
   def logCleanerMinCleanRatio = getDouble(CleanerConfig.LOG_CLEANER_MIN_CLEAN_RATIO_PROP)
-  val logCleanerEnable = getBoolean(CleanerConfig.LOG_CLEANER_ENABLE_PROP)
   def logIndexSizeMaxBytes = getInt(ServerLogConfigs.LOG_INDEX_SIZE_MAX_BYTES_CONFIG)
   def logIndexIntervalBytes = getInt(ServerLogConfigs.LOG_INDEX_INTERVAL_BYTES_CONFIG)
   def logDeleteDelayMs = getLong(ServerLogConfigs.LOG_DELETE_DELAY_MS_CONFIG)

docs/upgrade.html

@@ -32,6 +32,14 @@ <h6><a id="upgrade_410_notable" href="#upgrade_410_notable">Notable changes in 4
                     </li>
                 </ul>
             </li>
+            <li><b>Broker</b>
+                <ul>
+                    <li>
+                        The configuration <code>log.cleaner.enable</code> is deprecated. Users should no longer set it to <code>false</code> to prepare for future removal.
+                        For further details, please refer to <a href="https://cwiki.apache.org/confluence/x/XAyWF">KIP-1148</a>.
+                    </li>
+                </ul>
+            </li>
             <li><b>Producer</b>
                 <ul>
                     <li>The <code>flush</code> method now detects potential deadlocks and prohibits its use inside a callback. This change prevents unintended blocking behavior, which was a known risk in earlier versions.

storage/src/main/java/org/apache/kafka/storage/internals/log/CleanerConfig.java

@@ -50,6 +50,7 @@ public class CleanerConfig {
     public static final String LOG_CLEANER_DEDUPE_BUFFER_LOAD_FACTOR_PROP = ServerTopicConfigSynonyms.LOG_CLEANER_PREFIX + "io.buffer.load.factor";
     public static final String LOG_CLEANER_BACKOFF_MS_PROP = ServerTopicConfigSynonyms.LOG_CLEANER_PREFIX + "backoff.ms";
     public static final String LOG_CLEANER_MIN_CLEAN_RATIO_PROP = ServerTopicConfigSynonyms.serverSynonym(TopicConfig.MIN_CLEANABLE_DIRTY_RATIO_CONFIG);
+    @Deprecated(since = "4.1")
     public static final String LOG_CLEANER_ENABLE_PROP = ServerTopicConfigSynonyms.LOG_CLEANER_PREFIX + "enable";
     public static final String LOG_CLEANER_DELETE_RETENTION_MS_PROP = ServerTopicConfigSynonyms.serverSynonym(TopicConfig.DELETE_RETENTION_MS_CONFIG);
     public static final String LOG_CLEANER_MIN_COMPACTION_LAG_MS_PROP = ServerTopicConfigSynonyms.serverSynonym(TopicConfig.MIN_COMPACTION_LAG_MS_CONFIG);
@@ -68,7 +69,9 @@ public class CleanerConfig {
     public static final String LOG_CLEANER_DEDUPE_BUFFER_LOAD_FACTOR_DOC = "Log cleaner dedupe buffer load factor. The percentage full the dedupe buffer can become. A higher value " +
             "will allow more log to be cleaned at once but will lead to more hash collisions";
     public static final String LOG_CLEANER_BACKOFF_MS_DOC = "The amount of time to sleep when there are no logs to clean";
-    public static final String LOG_CLEANER_ENABLE_DOC = "Enable the log cleaner process to run on the server. Should be enabled if using any topics with a cleanup.policy=compact including the internal offsets topic. If disabled those topics will not be compacted and continually grow in size.";
+    @Deprecated(since = "4.1")
+    public static final String LOG_CLEANER_ENABLE_DOC = "This configuration has been deprecated and will be removed in Kafka 5.0. Users should not set it to false to prepare for its future removal. " +
+            "Enable the log cleaner process to run on the server. Should be enabled if using any topics with a cleanup.policy=compact including the internal offsets topic. If disabled those topics will not be compacted and continually grow in size.";
     public static final String LOG_CLEANER_DELETE_RETENTION_MS_DOC = "The amount of time to retain tombstone message markers for log compacted topics. This setting also gives a bound " +
             "on the time in which a consumer must complete a read if they begin from offset 0 to ensure that they get a valid snapshot of the final stage (otherwise  " +
             "tombstones messages may be collected before a consumer completes their scan).";