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Matt Corgan commented on HBASE-5930: ------------------------------------ Periodically flushing the memstore seems like a good feature to me. Could also help clear out cold data from memory to make more room for bigger memstores on regions that are actually being used. A different solution to the underlying data loss issue might be to have a third client setting for WAL writing: NONE, SYNC, and ASYNC. ASYNC would write the data to a memory buffer, return success to the client, and another thread would flush the buffer to the WAL. The WAL would ideally only lag a few seconds behind the memstores, but some form of throttling would probably be needed. > Periodically flush the Memstore? > -------------------------------- > > Key: HBASE-5930 > URL: https://issues.apache.org/jira/browse/HBASE-5930 > Project: HBase > Issue Type: Improvement > Reporter: Lars Hofhansl > Priority: Minor > > A colleague of mine ran into an interesting issue. > He inserted some data with the WAL disabled, which happened to fit in the > aggregate Memstores memory. > Two weeks later he a had problem with the HDFS cluster, which caused the > region servers to abort. He found that his data was lost. Looking at the log > we found that the Memstores were not flushed at all during these two weeks. > Should we have an option to flush memstores periodically. There are obvious > downsides to this, like many small storefiles, etc. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira