Forced actions are currently async, and there's no feedback (this is currently being worked on for 0.90). I personnally look at the region servers' web UI metrics, when the compaction queue is at 0 on most machines then you know it's done. Ganglia makes this very easy as you can graph that for all the machines at the same time.
Compacting files involves rewriting them (into new files), so it is expected that the DFS usage grows during that time. Also files on HDFS are put in a "garbage can" and are only really deleted later. J-D On Wed, Jul 28, 2010 at 8:22 AM, Andrew Nguyen <[email protected]> wrote: > So, I ran the following command in the shells: > > alter 'tablename', {NAME=>'cfname', BLOCKSIZE=>1045876} > major_compact 'tablename' > > How do I know the major compact completed successfully? I saw that the > number of regions has grown quite a bit but I'm not quite sure to know when > it's all finished so that I can start the benchmarking. Another thing that I > noticed is after initiating the above, my DFS usage has continued to grow. I > had 800g total, and 300g used. After initiating the compaction, I am now at > 614M free... Is this expected? > > Thanks! > > On Jul 27, 2010, at 10:13 AM, Jean-Daniel Cryans wrote: > >> After altering the table, issue a major compaction on it and >> everything will be re-written with the new block size. > > > >
