I think.... HBase guarantees ACID semantics per-row That's why all CF have to flush when any one of them got memstore limit.
On Tue, Feb 25, 2014 at 1:28 PM, Bharath Vissapragada <[email protected] > wrote: > Hi Upendra, > > Your argument is correct, especially when there is an uneven data > distribution across CFs in a region and this is what is discussed in > HBASE-3149. > See comments from Stack, Nicholas & Lars. > > - Bharath > > > On Tue, Feb 25, 2014 at 12:24 PM, Upendra Yadav <[email protected] > >wrote: > > > Thanks... > > > > but for a region, why hbase need to flush other CF when one of the CF got > > memstore limit... > > > > > > On Tue, Feb 25, 2014 at 2:50 AM, Ted Yu <[email protected]> wrote: > > > > > Upendra: > > > In 0.89-fb branch, the following JIRA has been integrated: > > > > > > HBASE-3149 Make flush decisions per column family > > > > > > FYI > > > > > > > > > On Mon, Feb 24, 2014 at 2:11 PM, Upendra Yadav <[email protected] > > > >wrote: > > > > > > > Thanks for your Reply... > > > > > > > > But what is the benefits of different memstore for different CF, when > > all > > > > of them are going to flush on the same time? > > > > > > > > > > > > On Tue, Feb 25, 2014 at 1:23 AM, Jean-Marc Spaggiari < > > > > [email protected]> wrote: > > > > > > > > > 1. correct. > > > > > 2. Regions doesn't have memstores. Regions servers have memstores. > On > > > per > > > > > region per CF. all the memstores for a single regions are flush at > > the > > > > same > > > > > time when one is full, even if the others are not. > > > > > > > > > > HTH. > > > > > > > > > > JM > > > > > > > > > > > > > > > 2014-02-24 14:35 GMT-05:00 Upendra Yadav <[email protected]>: > > > > > > > > > > > 1. One region server can have more than one region for same table > > > > > > > > > > > > 2. Which one is correct: > > > > > > > > > > > > a) Each region has one memstore( and all CF for this region will > > > reside > > > > > in > > > > > > this single > > > > > > memstore) and if memstore size reached its configured limit it > will > > > > > > snapshot and flush... due to single CF all CF have to flush. > > > > > > > > > > > > b) Each region has n no. of CF and each CF has its own memstore. > > And > > > > when > > > > > > one CF's memstore get full it will snapshot and flush. And will > not > > > > force > > > > > > to flush other CF. > > > > > > > > > > > > I read the current document some days before and now once again i > > got > > > > > that > > > > > > doubts... > > > > > > > > > > > > > > > > > > > > > > > > -- > Bharath Vissapragada > <http://www.cloudera.com> >
