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From bridg...@apache.org
Subject drill git commit: edit to metadata caching doc
Date Wed, 03 Feb 2016 00:00:00 GMT
Repository: drill
Updated Branches:
  refs/heads/gh-pages 657633d7b -> 744a86fa6


edit to metadata caching doc


Project: http://git-wip-us.apache.org/repos/asf/drill/repo
Commit: http://git-wip-us.apache.org/repos/asf/drill/commit/744a86fa
Tree: http://git-wip-us.apache.org/repos/asf/drill/tree/744a86fa
Diff: http://git-wip-us.apache.org/repos/asf/drill/diff/744a86fa

Branch: refs/heads/gh-pages
Commit: 744a86fa678a58f978b5080f81651027449598f6
Parents: 657633d
Author: Bridget Bevens <bbevens@maprtech.com>
Authored: Tue Feb 2 15:56:56 2016 -0800
Committer: Bridget Bevens <bbevens@maprtech.com>
Committed: Tue Feb 2 15:56:56 2016 -0800

----------------------------------------------------------------------
 _docs/performance-tuning/026-hive-metadata-caching.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/drill/blob/744a86fa/_docs/performance-tuning/026-hive-metadata-caching.md
----------------------------------------------------------------------
diff --git a/_docs/performance-tuning/026-hive-metadata-caching.md b/_docs/performance-tuning/026-hive-metadata-caching.md
index efb613a..fd9d6c2 100644
--- a/_docs/performance-tuning/026-hive-metadata-caching.md
+++ b/_docs/performance-tuning/026-hive-metadata-caching.md
@@ -1,6 +1,6 @@
 ---
 title: "Hive Metadata Caching"
-date: 2016-02-02 21:21:09 UTC
+date: 2016-02-02 23:56:57 UTC
 parent: "Performance Tuning"
 ---
 
@@ -12,7 +12,7 @@ Drill caches Hive metadata in a Hive metastore client cache that resides
in Dril
 
 You can modify the TTL depending on how frequently the Hive metadata is updated. If the Hive
metadata is updated frequently, decrease the cache TTL value. If Hive metadata is updated
infrequently, increase the cache TTL value.
 
-For example, when you run a Drill query on a Hive table, Drill refreshes the cache 60 seconds
after the read on the table. If the table is updated in Hive within that 60 second window
and you issue another query on the table, the query would return incorrect results or an execution
error due to a stale cache. In such a scenario where Hive metadata is changing so quickly,
you may want to reduce the cache TTL to 2 seconds so that Drill refreshes the cache more frequently.
 
+For example, when you run a Drill query on a Hive table, Drill refreshes the cache 60 seconds
after the read on the table. If the table is updated in Hive within that 60 second window
and you issue another query on the table, Drill may not be aware of the changes until the
cache expires. In such a scenario where Hive metadata is changing so quickly, you could reduce
the cache TTL to 2 seconds so that Drill refreshes the cache more frequently.  
 
 ## Configuring the Cache  
 


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