bq. Don't go too low else it will never stop balancing the table each 5 minutes.
That shouldn't happen - balancer will stop if the difference between highest number of regions and lowest becomes 1. Cheers On Wed, Feb 20, 2013 at 4:19 AM, Jean-Marc Spaggiari < jean-m...@spaggiari.org> wrote: > Hi Raymond, > > Yes, tables are balanced on by one. Balancer is taking one table, > looking if it's already balancer or not, do the required move if any > is needed, and then move to the next table. > > In your example, average is 23.25. 20% is 4.65. So everything between > 18.6 and 27.9 should be ok. So balancer should remove some regions for > the 3rd server (19 i/30/23/21). > > If you want to have that more evenly balanced, reduce the > hbase.regions.slop value to something lower, like 0.1 or even 0.05. > Don't go too low else it will never stop balancing the table each 5 > minutes. > > JM > > 2013/2/20, Liu, Raymond <raymond....@intel.com>: > > You mean slop is also base on per table? > > Weird, then it should work for my case.... let me check again. > > > > Best Regards, > > Raymond Liu > > > >> > >> bq. On a 3000 region cluster > >> > >> Balancing is per-table. Meaning total number of regions doesn't come > into > >> play. > >> > >> On Tue, Feb 19, 2013 at 7:55 PM, Liu, Raymond <raymond....@intel.com> > >> wrote: > >> > >> > Hmm, in order to have the 96 region table be balanced within 20% On a > >> > 3000 region cluster when all other table is balanced. > >> > > >> > the slop will need to be around 20%/30, say 0.006? won't it be too > >> > small? > >> > > >> > > > >> > > Yes, Raymond. > >> > > You should lower sloppiness. > >> > > > >> > > On Tue, Feb 19, 2013 at 7:48 PM, Liu, Raymond > >> > > <raymond....@intel.com> > >> > > wrote: > >> > > > >> > > > I mean region number is small. > >> > > > > >> > > > Overall I have say 3000 region on 4 node, while this table only > >> > > > have > >> > > > 96 region. It won't be 24 for each region server, instead , will > >> > > > be something like 19/30/23/21 etc. > >> > > > > >> > > > This means that I need to limit the slop to 0.02 etc? so that the > >> > > > balancer actually run on this table? > >> > > > > >> > > > Best Regards, > >> > > > Raymond Liu > >> > > > > >> > > > From: Marcos Ortiz [mailto:mlor...@uci.cu] > >> > > > Sent: Wednesday, February 20, 2013 11:44 AM > >> > > > To: user@hbase.apache.org > >> > > > Cc: Liu, Raymond > >> > > > Subject: Re: Is there any way to balance one table? > >> > > > > >> > > > What is the size of your table? > >> > > > On 02/19/2013 10:40 PM, Liu, Raymond wrote: > >> > > > Hi > >> > > > > >> > > > I do call balancer, while it seems it doesn't work. Might due to > >> > > > this table is small and overall region number difference is within > >> > threshold? > >> > > > > >> > > > -----Original Message----- > >> > > > From: Jean-Marc Spaggiari [mailto:jean-m...@spaggiari.org] > >> > > > Sent: Wednesday, February 20, 2013 10:59 AM > >> > > > To: user@hbase.apache.org > >> > > > Subject: Re: Is there any way to balance one table? > >> > > > > >> > > > Hi Liu, > >> > > > > >> > > > Why did not you simply called the balancer? If other tables are > >> > > > already balanced, it should not touch them and will only balance > >> > > > the table which is not balancer? > >> > > > > >> > > > JM > >> > > > > >> > > > 2013/2/19, Liu, Raymond <raymond....@intel.com>: > >> > > > I choose to move region manually. Any other approaching? > >> > > > > >> > > > > >> > > > 0.94.1 > >> > > > > >> > > > Any cmd in shell? Or I need to change balance threshold to 0 an > >> > > > run global balancer cmd in shell? > >> > > > > >> > > > > >> > > > > >> > > > Best Regards, > >> > > > Raymond Liu > >> > > > > >> > > > -----Original Message----- > >> > > > From: Ted Yu [mailto:yuzhih...@gmail.com] > >> > > > Sent: Wednesday, February 20, 2013 9:09 AM > >> > > > To: user@hbase.apache.org > >> > > > Subject: Re: Is there any way to balance one table? > >> > > > > >> > > > What version of HBase are you using ? > >> > > > > >> > > > 0.94 has per-table load balancing. > >> > > > > >> > > > Cheers > >> > > > > >> > > > On Tue, Feb 19, 2013 at 5:01 PM, Liu, Raymond > >> > > > <raymond....@intel.com> > >> > > > wrote: > >> > > > > >> > > > Hi > >> > > > > >> > > > Is there any way to balance just one table? I found one of my > >> > > > table is not balanced, while all the other table is balanced. So I > >> > > > want to fix this table. > >> > > > > >> > > > Best Regards, > >> > > > Raymond Liu > >> > > > > >> > > > > >> > > > > >> > > > > >> > > > -- > >> > > > Marcos Ortiz Valmaseda, > >> > > > Product Manager && Data Scientist at UCI > >> > > > Blog: http://marcosluis2186.posterous.com > >> > > > Twitter: @marcosluis2186 > >> > > > > >> > > > >
