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Hadoop QA commented on HBASE-12219: ----------------------------------- {color:red}-1 overall{color}. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12678443/HBASE-12219-0.99.patch against trunk revision . ATTACHMENT ID: 12678443 {color:green}+1 @author{color}. The patch does not contain any @author tags. {color:green}+1 tests included{color}. The patch appears to include 8 new or modified tests. {color:red}-1 patch{color}. The patch command could not apply the patch. Console output: https://builds.apache.org/job/PreCommit-HBASE-Build/11539//console This message is automatically generated. > Cache more efficiently getAll() and get() in FSTableDescriptors > --------------------------------------------------------------- > > Key: HBASE-12219 > URL: https://issues.apache.org/jira/browse/HBASE-12219 > Project: HBase > Issue Type: Bug > Components: master > Affects Versions: 0.94.24, 0.99.1, 0.98.6.1 > Reporter: Esteban Gutierrez > Assignee: Esteban Gutierrez > Labels: scalability > Attachments: HBASE-12219-0.99.patch, HBASE-12219-v1.patch, > HBASE-12219-v1.patch, HBASE-12219.v0.txt, HBASE-12219.v2.patch, > HBASE-12219.v3.patch, list.png > > > Currently table descriptors and tables are cached once they are accessed for > the first time. Next calls to the master only require a trip to HDFS to > lookup the modified time in order to reload the table descriptors if > modified. However in clusters with a large number of tables or concurrent > clients and this can be too aggressive to HDFS and the master causing > contention to process other requests. A simple solution is to have a TTL > based cached for FSTableDescriptors#getAll() and > FSTableDescriptors#TableDescriptorAndModtime() that can allow the master to > process those calls faster without causing contention without having to > perform a trip to HDFS for every call. to listtables() or getTableDescriptor() -- This message was sent by Atlassian JIRA (v6.3.4#6332)