Does this have a significant increase on HBase performances? And what are the "risks" associated with short-circuit activation (if any)? No risks of corrupting data?
Can this be activated after tables are already populated? JM 2013/1/27, Ted <[email protected]>: > For hbase internal checksum, it is not in hbase 0.92.x release. > > Please use 0.94.2 or newer release. > > Thanks > > On Jan 27, 2013, at 2:29 PM, David Koch <[email protected]> wrote: > >> Hello, >> >> I read about "short circuit reads" in the HBase documentation's >> performance >> section[1] and was wondering what people's experiences were using this in >> a >> production setting. >> >> Also, >> >> 1. Since only one dedicated user can take advantage of the feature do you >> launch all jobs as this user? >> 2. Can dfs.client.read.shortcircuit be set to false for jobs wich are not >> launched by the short-circuit user in order to avoid exceptions? In other >> words - can this setting be overriden by the client configuration's >> hbase-site.xml? >> 3. In the same context, it is suggested to enable HBase internal >> checksums[2]. Is this a feature which can be enabled in HBase 0.92.1 >> which >> is part of the Cloudera 4.1.x release? >> >> Thank you, >> >> /David >> >> [1] http://hbase.apache.org/book/perf.hdfs.html#ftn.d2145e7370 >> [2] https://issues.apache.org/jira/browse/HBASE-5074 >
