From 0914fcca312b5e9d20bcf1b6633bc13c9034ba46 Mon Sep 17 00:00:00 2001
From: Xiao Chen <xiao@apache.org>
Date: Thu, 2 Feb 2017 10:08:27 -0800
Subject: [PATCH] HDFS-11363. Need more diagnosis info when seeing Slow
 waitForAckedSeqno.

---
 .../src/main/java/org/apache/hadoop/hdfs/DataStreamer.java   | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DataStreamer.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DataStreamer.java
index ef5d21a7fb..8e6eb63abe 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DataStreamer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DataStreamer.java
@@ -865,8 +865,9 @@ void waitForAckedSeqno(long seqno) throws IOException {
       }
       long duration = Time.monotonicNow() - begin;
       if (duration > dfsclientSlowLogThresholdMs) {
-        LOG.warn("Slow waitForAckedSeqno took " + duration
-            + "ms (threshold=" + dfsclientSlowLogThresholdMs + "ms)");
+        LOG.warn("Slow waitForAckedSeqno took {}ms (threshold={}ms). File being"
+                + " written: {}, block: {}, Write pipeline datanodes: {}.",
+            duration, dfsclientSlowLogThresholdMs, src, block, nodes);
       }
     }
   }