From 3fe79e1db84391cb17dbed6b579fe9c803b3d1c2 Mon Sep 17 00:00:00 2001 From: Colin Patrick Mccabe Date: Mon, 4 May 2015 12:50:29 -0700 Subject: [PATCH] HDFS-7397. Add more detail to the documentation for the conf key "dfs.client.read.shortcircuit.streams.cache.size" (Brahma Reddy Battula via Colin P. McCabe) --- hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt | 4 ++++ .../hadoop-hdfs/src/main/resources/hdfs-default.xml | 2 +- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt index a365b865b6..21d73bad87 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt +++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt @@ -500,6 +500,10 @@ Release 2.8.0 - UNRELEASED HDFS-8249. Separate HdfsConstants into the client and the server side class. (wheat9) + HDFS-7397. Add more detail to the documentation for the conf key + "dfs.client.read.shortcircuit.streams.cache.size" (Brahma Reddy Battula via + Colin P. McCabe) + OPTIMIZATIONS HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml index f03c0fb60d..e3e432304a 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml +++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml @@ -2063,7 +2063,7 @@ 256 The DFSClient maintains a cache of recently opened file descriptors. - This parameter controls the size of that cache. + This parameter controls the maximum number of file descriptors in the cache. Setting this higher will use more file descriptors, but potentially provide better performance on workloads involving lots of seeks.