5000 regions in 10RS it's 500 regions per RS just for this table... If are above the recommended limit. How big are your regions? I mean, MAXFILESIZE?
JM 2015-10-09 9:46 GMT-04:00 Anil Gupta <[email protected]>: > Hi Nicolas, > > For a table with 5k regions, it should not take more than 10 min for alter > table operations. > Also, in HBase 1.0+, alter table operations does not require disabling the > table. So, you are encouraged to upgrade. > > Sent from my iPhone > > > On Oct 9, 2015, at 1:15 AM, Nicolae Marasoiu < > [email protected]> wrote: > > > > Hi, > > > > Indeed, we have tables with 1-5000 regions, distributed on 10-15 RSs. > > > > A few hours are sufficient to do the alter one a single such table, > right? > > > > Thanks, > > Nicu > > > > ________________________________________ > > From: Jean-Marc Spaggiari <[email protected]> > > Sent: Thursday, October 8, 2015 10:19 PM > > To: user > > Subject: Re: alter column family - possible operational impacts on big > tables > > > > Hi Nicu, > > > > Indeed, with 0.94 you have to disable the table before doing the alter. > > However, for 30 regions, it should be pretty fast. When you say 30+, are > > you talking about like 1K regions? Or more like 32? The alter will only > > update the meta table, so not that much impact on the servers. And no > > compactions required for that. The ttl will only take effect at the next > > compaction by, as you said, filtering out more records. > > > > JM > > > > 2015-10-08 10:49 GMT-04:00 Nicolae Marasoiu < > [email protected]>: > > > >> Hi, > >> > >> > >> If we run at night an alter column family, set ttl, my understanding is > >> that it will disable the table, make the alter, and re-enable the table, > >> which can be some time for large tables with 30+ regions (hbase version > >> 0.94 [image: ☹] ). > >> > >> > >> Do you have any advice about this? How long can it take per region? What > >> is the operational hit at the time of the alter command being issued, > and > >> what when compaction runs on the table? I imagine that compaction is not > >> too affected by this, just by filtering out more records when re-writing > >> the new HFiles, is this correct? > >> > >> > >> Thanks, > >> > >> Nicu > >> >
