HDDS-1959. Decrement purge interval for Ratis logs in datanode (#1301)

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ScmConfigKeys.java

@@ -119,7 +119,7 @@ public final class ScmConfigKeys {
       "dfs.container.ratis.log.purge.gap";
   // TODO: Set to 1024 once RATIS issue around purge is fixed.
   public static final int DFS_CONTAINER_RATIS_LOG_PURGE_GAP_DEFAULT =
-      1000000000;
+      1000000;
   // expiry interval stateMachineData cache entry inside containerStateMachine
   public static final String
       DFS_CONTAINER_RATIS_STATEMACHINEDATA_CACHE_EXPIRY_INTERVAL =

hadoop-hdds/common/src/main/resources/ozone-default.xml

@@ -106,7 +106,7 @@
   </property>
   <property>
     <name>dfs.container.ratis.log.purge.gap</name>
-    <value>1000000000</value>
+    <value>1000000</value>
     <tag>OZONE, DEBUG, CONTAINER, RATIS</tag>
     <description>Purge gap between the last purged commit index
       and the current index, when the leader decides to purge its log.