Ted, Why would we use that merge tool when hbck will repair that? Should we throw a warning and tell the user to run repair first? On Mar 16, 2013 9:17 AM, "Ted" <[email protected]> wrote:
> Chunhui replied to this question on review board. > > Basically the force option is to repair overlapping regions or table with > hole in its regions. > > Personally I think online merge should detect merging regions with hole in > between them and not require force flag in that case because logically > they're adjacent. > > Cheers > > On Mar 16, 2013, at 5:52 AM, Jean-Marc Spaggiari <[email protected]> > wrote: > > > Hi Ted, > > > > I jut gave it a look. > > > > I have updated it on the RB. > > > > Overall, this is very good and I'm eager to see that integrated! I'm > > waiting for this feature since the beginning ;) > > > > Regarding non adjacent regions merge? Will the system still be > > consistent after that? Or will hbck report some regions overlaps? > > > > JM > > > > > > 2013/3/16 Ted Yu <[email protected]>: > >> Hi, > >> On behalf of Chunhui, I am requesting review for HBASE-7403 Online > Merge. > >> > >> This JIRA was created 3 months ago. > >> Chunhui has responded to review comments very promptly, including a > major > >> rewrite around the time split transaction was rewritten. > >> > >> This feature has widely been requested. I feel the patch is mostly > ready to > >> go in. > >> Here is brief recap of the steps. > >> > >> Process of merging two regions: > >> > >> a.client sends RPC (dispatch merging regions) to master > >> b.master moves the regions together (on the regionserver where the more > >> heavily loaded region resided) > >> c.master sends RPC (merge regions) to this regionserver > >> d.Regionserver executes the region merge transaction in the thread pool > >> > >> I think step b is a nice simplification for the problem. In previous > >> versions of the patch, the two merging regions stay on respective > servers > >> which required more complex coordination through zookeeper. > >> > >> High level comment as well as detailed review are both welcome. > >> > >> Thanks >
