They would move over to live region servers. Cheers
On Dec 23, 2012, at 2:59 PM, Brennon Church <[email protected]> wrote: > I'm curious. If I disable the hbase balancer, what happens when a > regionserver goes offline? Will those regions get moved over to the > remaining hosts as would normally be the case? Or will they remain > unavailable until the balancer is run manually? > > Thanks. > > --Brennon > > On 12/22/12 5:48 AM, Ted Yu wrote: >> When region splits, the daughter regions would be placed on the same server >> as parent region. >> You also need to consider the case where new server crashes and its regions >> are moved to older system. >> >> In HBASE-5231 <https://issues.apache.org/jira/browse/HBASE-5231> you can >> find a patch which does per table load balancing. You can modify that code >> to move regions of selected table to pre-defined group of servers >> (specified through configuration). >> >> Cheers >> >> On Fri, Dec 21, 2012 at 11:01 PM, Brennon Church <[email protected]> wrote: >> >>> I do allow regions from other tables on the newer servers. The issue >>> stems from a single table that habitually causes hot regions. Not such a >>> problem on the new servers, but when those regions hit the older systems >>> bad things happen. I think the proper long-term solution is to change the >>> code writing to the table, but that's not something that can be done right >>> now, so I'm looking for the second best option. >>> >>> The HBASE-6721 option sounds perfect, if I'm reading it correctly. It >>> doesn't quite fit my use case, but would solve the problem regardless. >>> >>> If I understand the balancer part correctly, a possible but ugly (IMHO) >>> option would be to move the region(s) causing trouble over to the more >>> powerful servers then disable automatic balancing. Would region splits >>> then remain on the same system as the original region? If so, it would >>> work around the problem but at the expense of having to manually move >>> regions around more frequently to keep everything else balanced. >>> >>> Thanks. >>> >>> --Brennon >>> >>> >>> On 12/21/12 8:48 PM, Ted Yu wrote: >>> >>>> Brennon: >>>> I forgot to ask you about other tables you have. Do you allow regions of >>>> other tables to also be assigned to this group of newer servers ? >>>> If you do, there is possibility that the combined load on such new servers >>>> would make response from them slow. >>>> >>>> Cheers >>>> >>>> On Fri, Dec 21, 2012 at 8:28 PM, Ted Yu <[email protected]> wrote: >>>> >>>> What you describe is akin to HBASE-6721 region server group. >>>>> Basically you want this table to be bound to group of region servers. >>>>> >>>>> Development for 0.94 is on-going, to my knowledge. >>>>> >>>>> Cheers >>>>> >>>>> >>>>> On Fri, Dec 21, 2012 at 7:30 PM, Brennon Church <[email protected] >>>>>> wrote: >>>>> 0.92.0 >>>>>> I was looking at the balancer option. I'm loathe to turn the automatic >>>>>> balancer off and handle it manually as we have a lot of regions. Is >>>>>> that >>>>>> the option you were thinking of? Or am I missing something? >>>>>> >>>>>> Thanks. >>>>>> >>>>>> --Brennon >>>>>> >>>>>> >>>>>> On 12/21/12 4:19 PM, Ted Yu wrote: >>>>>> >>>>>> Currently there is no such capability - you may need to customize load >>>>>>> balancer. >>>>>>> >>>>>>> What version of HBase are you using ? >>>>>>> >>>>>>> Cheers >>>>>>> >>>>>>> On Fri, Dec 21, 2012 at 3:54 PM, Brennon Church <[email protected]> >>>>>>> wrote: >>>>>>> >>>>>>> I'm curious, is there any concept of hosting regions from a given >>>>>>> table >>>>>>> >>>>>>>> only on a single host or subset of hosts in a cluster? In our case we >>>>>>>> have >>>>>>>> a heavily-used table that can cause problems for the older systems in >>>>>>>> our >>>>>>>> cluster. Newer systems would have less trouble, so I'd like to >>>>>>>> restrict >>>>>>>> regions for that one table only to those more powerful servers. >>>>>>>> >>>>>>>> Thanks. >>>>>>>> >>>>>>>> --Brennon >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>> > >
