Demai: You can find description of compaction-related parameters in: http://hbase.apache.org/book.html#compaction
Cheers On Thu, Mar 6, 2014 at 10:44 AM, lars hofhansl <[email protected]> wrote: > The problem is not major compactions, but compactions that compact a lot > of files. > > > HBase will always compact in the background (minor compactions). > If a minor compaction needs to compact all files anyway it is promoted to > a major compaction. > There is no performance penalty to that, just that if all files are > compacted anyway might as well get rid of the delete markers in the process. > > > So rather than avoiding major compactions, what you want to avoid are > compactions that touch a lot of (or all) files. You'd need to tweak the > compaction setting - which is an art in itself. You could lower the > compaction ratio, or increase the number of store files before compations > start, pick a different compaction strategy, etc. > > > -- Lars > > > > ________________________________ > From: Demai Ni <[email protected]> > To: "[email protected]" <[email protected]> > Sent: Thursday, March 6, 2014 10:28 AM > Subject: turn off size-based Major Compaction? > > > hi, folks, > > Is there a way to turn off Major Compaction, for sure? > > We are using 96.0, and set hbase.hregion.majorcompaction is 0. The > intention was to only run major compaction manually. It turns out after > heavy load, major compaction still occur as shown in WebUI. > > After a bit search, I read this discussion: > > http://apache-hbase.679495.n3.nabble.com/Major-Compaction-Concerns-td3642142.html > , > which indicated that there are three way to trigger major compaction: > 1) user issued, (that is manually, such in hbase shell) > 2) timed, (that is hbase.hregion.majorcompaction) > 3) size-based. > > Is there a way to prevent or configure the 3) method? I found > hbase.hstore.compaction.max, > but it is for minor compaction. > > So the question is: what configuration for the *size-based* on > *Major*compaction? > > Many thanks > > Demai
