Hello, We disabled automated major compactions by setting hbase.hregion.majorcompaction=0. This was to avoid issues during buik import of data since compactions seemed to cause the running imports to crash. However, even after disabling, region server logs still show compactions going on, as well as aborted compactions. We also get compaction queue size warnings in Cloudera Manager.
Why is this the case? To be fair, we only disabled automated compactions AFTER the import failed for the first time (yes, HBase was restarted) so maybe there are some trailing compactions, but the queue size keeps increasing which I guess should not be the case. Then again, I don't know how aborted compactions are counted - i.e not sure whether or not to trust the metrics on this. A bit more about what I am trying to accomplish: I am bulk loading about 100 indexed .lzo files with 20 * 10^6 Key-Value (0.5kb) each into an HBase table. Each file is loaded by a separate Mapper job, several of these jobs run in parallel to make sure all task trackers are used. Key distribution is the same in each file so even region growth is to be expected. We did not pre-split the table as it does not seem to have been a limiting factor earlier. On a related note. What if any experience do other HBase/Cloudera users have with the Snapshotting feature detailed below? http://www.cloudera.com/content/cloudera-content/cloudera- docs/CDH4/4.2.0/CDH4-Installation-Guide/cdh4ig_topic_20_12.html We need of a robust way to do inter-cluster cloning/back-up of tables, preferably without taking the source table offline or impacting performance of the source cluster. We only use HDFS files for importing because the CopyTable job needs to run on the source cluster and cannot be resumed once it fails. Thanks, /David
