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Mike Drob commented on HBASE-20674: ----------------------------------- v4: adding tests to verify on HDFS and Local file system. Logs show falling back to DFS checksums when hbase checksums failed. > clean up short circuit read logic and docs > ------------------------------------------ > > Key: HBASE-20674 > URL: https://issues.apache.org/jira/browse/HBASE-20674 > Project: HBase > Issue Type: Bug > Components: regionserver > Affects Versions: 2.0.0 > Reporter: Mike Drob > Assignee: Mike Drob > Priority: Major > Attachments: HBASE-20674.patch, HBASE-20674.v2.patch, > HBASE-20674.v3.patch, HBASE-20674.v4.patch > > > Mailing list discussion at > https://lists.apache.org/thread.html/f6f73df0ceae29f762f9b9088e3ffd0bf8f109d3dd692df100bf4fd6@%3Cdev.hbase.apache.org%3E > There are several inconsistencies between how our docs claim we do things and > how we actually do things. > There are two docs sections that attempt to address how SCR should work. > dfs.client.read.shortcircuit.skip.checksum is advised to set to true, but our > code in separate places ignores it and then later sets it to true anyway. > CommonFSUtils and FSUtils duplicate code related to SCR setup. > There is a workaround in HFileSystem for a bug that's been fixed in all > versions of hadoop that we support. (HADOOP-9307) > We suggest setting dfs.client.read.shortcircuit.buffer.size to a value that > is very close to what we'd set it to anyway, without clearly explaining why > this is important. > There are other properties that we claim are important, but we don't offer > any suggestions or explanations. -- This message was sent by Atlassian JIRA (v7.6.3#76005)