If cluster restarts, master still needs to assign such regions. This would affect MTTR.
Otherwise in a stable cluster, they shouldn't consume much resource. Cheers On Oct 14, 2014, at 3:45 AM, Serega Sheypak <[email protected]> wrote: > Ok, I got. > And in general, region which has no R/W requests doesn't consume ny > resources except record in META? > > 2014-10-14 13:42 GMT+04:00 Ted Yu <[email protected]>: > >> In 0.94, load balancer doesn't take load each region receives into >> account. It only considers the number of regions as the sole criteria for >> balancing. >> >> Thus the high number of unused regions may cause imbalance. >> >> Please consider reducing unused regions. >> >> Cheers >> >> On Oct 14, 2014, at 2:33 AM, Serega Sheypak <[email protected]> >> wrote: >> >>> We are using CDH 4.6 (hbase-0.94.15+86) >>> Regions are balanced. >>> - Read/write request are pretty even, >>> - count or regions per RegionServer is pretty even. >>> - there are no "hot spots" >>> >>> >>> 2014-10-14 12:50 GMT+04:00 Qiang Tian <[email protected]>: >>> >>>> region unbalanced? >>>> which hbase release? >>>> >>>> >>>> On Tue, Oct 14, 2014 at 3:39 PM, Serega Sheypak < >> [email protected]> >>>> wrote: >>>> >>>>> Hi, we have 10 nodes cluster with 10HDD, 256 GB RAM and 10HDD 3TB each. >>>>> Suddenly we met write perfomance issues. >>>>> >>>>> Our workload is: >>>>> 1. We have 100+ region table for write load. It has constant set of >> keys >>>>> (~6* 10^7) and we write "updates". No versions or stuff like that >>>>> 2. We have several read-only tables, theirs size could be from 1 egion >> up >>>>> to 256 regions. >>>>> 3. We have several non-used tables theirs size could be from 1 region >> up >>>>> to 256 regions. These tables are previous versions of read-only tables. >>>>> >>>>> Right now each RegionServer serves >100 regions, but only half of them >>>> are >>>>> active. Really nothing changed for the last few weeks, we got more >>>> non-used >>>>> tables, but quantity on active read-only tables is the same, single >>>>> wirte-only table dodn't get more bytes to write. >>>>> >>>>> Can big count of non-used(!!!) regions affect write/read perfomance for >>>>> tables which are in use. >>
