From 659f25bc2f86667df7de19f152921200c7cff7ad Mon Sep 17 00:00:00 2001
From: Nhat Nguyen <nhat.nguyen@elastic.co>
Date: Tue, 30 Apr 2019 12:39:14 -0400
Subject: [PATCH] shouldRollGeneration should execute under read lock

---
 .../main/java/org/elasticsearch/index/translog/Translog.java | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/server/src/main/java/org/elasticsearch/index/translog/Translog.java b/server/src/main/java/org/elasticsearch/index/translog/Translog.java
index 841201b321549..5e07c43ff6925 100644
--- a/server/src/main/java/org/elasticsearch/index/translog/Translog.java
+++ b/server/src/main/java/org/elasticsearch/index/translog/Translog.java
@@ -561,9 +561,10 @@ public Location add(final Operation operation) throws IOException {
      * @return {@code true} if the current generation should be rolled to a new generation
      */
     public boolean shouldRollGeneration() {
-        final long size = this.current.sizeInBytes();
         final long threshold = this.indexSettings.getGenerationThresholdSize().getBytes();
-        return size > threshold;
+        try (ReleasableLock ignored = readLock.acquire()) {
+            return this.current.sizeInBytes() > threshold;
+        }
     }
 
     /**