[improve][conf] Change the default value of readOnlyModeOnAnyDiskFullEnabled to true (#4520)

* [improve][conf] Change the default value of readOnlyModeOnAnyDiskFullEnabled to true

Author: liangyepianzhou

bookkeeper-server/src/main/java/org/apache/bookkeeper/conf/ServerConfiguration.java

@@ -2462,12 +2462,12 @@ public ServerConfiguration setReadOnlyModeOnAnyDiskFullEnabled(boolean enabled)
     }
 
     /**
-     * Get whether read-only mode is enable when any disk is full. The default is false.
+     * Get whether read-only mode is enable when any disk is full. The default is true.
      *
      * @return boolean
      */
     public boolean isReadOnlyModeOnAnyDiskFullEnabled() {
-        return getBoolean(READ_ONLY_MODE_ON_ANY_DISK_FULL_ENABLED, false);
+        return getBoolean(READ_ONLY_MODE_ON_ANY_DISK_FULL_ENABLED, true);
     }
 
     /**

bookkeeper-server/src/test/java/org/apache/bookkeeper/bookie/LedgerDirsManagerTest.java

@@ -414,7 +414,7 @@ public void testLedgerDirsMonitorHandlingWithMultipleLedgerDirectories() throws
         // one dir usagespace above storagethreshold, another dir below storagethreshold
         // should still be writable
         setUsageAndThenVerify(curDir1, nospace + 0.02f, curDir2, nospace - 0.05f, mockDiskChecker,
-                mockLedgerDirsListener, false);
+                mockLedgerDirsListener, true);
 
         // should remain readonly
         setUsageAndThenVerify(curDir1, nospace + 0.05f, curDir2, nospace + 0.02f, mockDiskChecker,
@@ -438,7 +438,7 @@ public void testLedgerDirsMonitorHandlingWithMultipleLedgerDirectories() throws
         // overall diskusage is less than lwm
         // should goto readwrite
         setUsageAndThenVerify(curDir1, lwm - 0.17f, curDir2, nospace + 0.03f, mockDiskChecker, mockLedgerDirsListener,
-                false);
+                true);
         assertEquals("Only one LedgerDir should be writable", 1, dirsManager.getWritableLedgerDirs().size());
 
         // bring both the dirs below lwm

bookkeeper-server/src/test/java/org/apache/bookkeeper/test/ReadOnlyBookieTest.java

@@ -103,6 +103,7 @@ public void testBookieShouldServeAsReadOnly() throws Exception {
     public void testBookieShouldTurnWritableFromReadOnly() throws Exception {
         killBookie(0);
         baseConf.setReadOnlyModeEnabled(true);
+        baseConf.setReadOnlyModeOnAnyDiskFullEnabled(false);
         baseConf.setDiskCheckInterval(Integer.MAX_VALUE);
         startNewBookie();
         LedgerHandle ledger = bkc.createLedger(2, 2, DigestType.MAC,

conf/bk_server.conf

@@ -181,8 +181,8 @@ extraServerComponents=
 # If "readOnlyModeOnAnyDiskFullEnabled=true" then on any ledger disks full, bookie will be converted
 # to read-only mode and serve only read requests. When all disks recovered,
 # the bookie will be converted to read-write mode.Otherwise it will obey the `readOnlyModeEnabled` behavior.
-# By default this will be disabled.
-# readOnlyModeOnAnyDiskFullEnabled=false
+# By default this will be enable.
+# readOnlyModeOnAnyDiskFullEnabled=true
 
 #############################################################################
 ## Netty server settings