From 80a797fc4fad31524291ea0475f1a58bedacb83b Mon Sep 17 00:00:00 2001
From: kimchy <kimchy@gmail.com>
Date: Wed, 9 Mar 2011 14:17:34 +0200
Subject: [PATCH] Update Settings: Allow to dynamically update `index.translog`
 settings, closes #765.

---
 .../index/translog/TranslogService.java       | 37 +++++++++++++++++--
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/TranslogService.java b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/TranslogService.java
index d0d6d8e0345..5828abe1dcb 100644
--- a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/TranslogService.java
+++ b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/TranslogService.java
@@ -28,6 +28,7 @@ import org.elasticsearch.index.engine.Engine;
 import org.elasticsearch.index.engine.EngineClosedException;
 import org.elasticsearch.index.engine.FlushNotAllowedEngineException;
 import org.elasticsearch.index.settings.IndexSettings;
+import org.elasticsearch.index.settings.IndexSettingsService;
 import org.elasticsearch.index.shard.AbstractIndexShardComponent;
 import org.elasticsearch.index.shard.IndexShardState;
 import org.elasticsearch.index.shard.ShardId;
@@ -45,23 +46,28 @@ public class TranslogService extends AbstractIndexShardComponent {
 
     private final ThreadPool threadPool;
 
+    private final IndexSettingsService indexSettingsService;
+
     private final IndexShard indexShard;
 
     private final Translog translog;
 
-    private final int flushThresholdOperations;
+    private int flushThresholdOperations;
 
-    private final ByteSizeValue flushThresholdSize;
+    private ByteSizeValue flushThresholdSize;
 
-    private final TimeValue flushThresholdPeriod;
+    private TimeValue flushThresholdPeriod;
 
     private final TimeValue interval;
 
     private ScheduledFuture future;
 
-    @Inject public TranslogService(ShardId shardId, @IndexSettings Settings indexSettings, ThreadPool threadPool, IndexShard indexShard, Translog translog) {
+    private final ApplySettings applySettings = new ApplySettings();
+
+    @Inject public TranslogService(ShardId shardId, @IndexSettings Settings indexSettings, IndexSettingsService indexSettingsService, ThreadPool threadPool, IndexShard indexShard, Translog translog) {
         super(shardId, indexSettings);
         this.threadPool = threadPool;
+        this.indexSettingsService = indexSettingsService;
         this.indexShard = indexShard;
         this.translog = translog;
 
@@ -73,13 +79,36 @@ public class TranslogService extends AbstractIndexShardComponent {
         logger.debug("interval [{}], flush_threshold_ops [{}], flush_threshold_size [{}], flush_threshold_period [{}]", interval, flushThresholdOperations, flushThresholdSize, flushThresholdPeriod);
 
         this.future = threadPool.schedule(interval, ThreadPool.Names.SAME, new TranslogBasedFlush());
+
+        indexSettingsService.addListener(applySettings);
     }
 
 
     public void close() {
+        indexSettingsService.removeListener(applySettings);
         this.future.cancel(true);
     }
 
+    class ApplySettings implements IndexSettingsService.Listener {
+        @Override public void onRefreshSettings(Settings settings) {
+            int flushThresholdOperations = settings.getAsInt("index.translog.flush_threshold_ops", TranslogService.this.flushThresholdOperations);
+            if (flushThresholdOperations != TranslogService.this.flushThresholdOperations) {
+                logger.info("updating flush_threshold_ops from [{}] to [{}]", TranslogService.this.flushThresholdOperations, flushThresholdOperations);
+                TranslogService.this.flushThresholdOperations = flushThresholdOperations;
+            }
+            ByteSizeValue flushThresholdSize = settings.getAsBytesSize("index.translog.flush_threshold_size", TranslogService.this.flushThresholdSize);
+            if (!flushThresholdSize.equals(TranslogService.this.flushThresholdSize)) {
+                logger.info("updating flush_threshold_size from [{}] to [{}]", TranslogService.this.flushThresholdSize, flushThresholdSize);
+                TranslogService.this.flushThresholdSize = flushThresholdSize;
+            }
+            TimeValue flushThresholdPeriod = settings.getAsTime("index.translog.flush_threshold_period", TranslogService.this.flushThresholdPeriod);
+            if (!flushThresholdPeriod.equals(TranslogService.this.flushThresholdPeriod)) {
+                logger.info("updating flush_threshold_period from [{}] to [{}]", TranslogService.this.flushThresholdPeriod, flushThresholdPeriod);
+                TranslogService.this.flushThresholdPeriod = flushThresholdPeriod;
+            }
+        }
+    }
+
     private class TranslogBasedFlush implements Runnable {
 
         private volatile long lastFlushTime = System.currentTimeMillis();