Allan: I wonder how you deal with open issues such as HBASE-13535. >From your description, it seems your team fixed more DLR issues.
Cheers On Mon, Oct 17, 2016 at 11:37 PM, allanwin <[email protected]> wrote: > > > > Here is the thing. We have backported DLR(HBASE-7006) to our 0.94 > clusters in production environment(of course a lot of bugs are fixed and > it is working well). It is was proven to be a huge gain. When a large > cluster crash down, the MTTR improved from several hours to less than a > hour. Now, we want to move on to HBase1.x, and still we want DLR. This > time, we don't want to backport the 'backported' DLR to HBase1.x, but it > seems like that the community have determined to remove DLR... > > > The DLR feature is proven useful in our production environment, so I think > I will try to fix its issues in branch-1.x > > > > > > > At 2016-10-18 13:47:17, "Anoop John" <[email protected]> wrote: > >Agree with ur observation.. But DLR feature we wanted to get removed.. > >Because it is known to have issues.. Or else we need major work to > >correct all these issues. > > > >-Anoop- > > > >On Tue, Oct 18, 2016 at 7:41 AM, Ted Yu <[email protected]> wrote: > >> If you have a cluster, I suggest you turn on DLR and observe the effect > >> where fewer than half the region servers are up after the crash. > >> You would have first hand experience that way. > >> > >> On Mon, Oct 17, 2016 at 6:33 PM, allanwin <[email protected]> wrote: > >> > >>> > >>> > >>> > >>> Yes, region replica is a good way to improve MTTR. Specially if one or > two > >>> servers are down, region replica can improve data availability. But > for big > >>> disaster like 1/3 or 1/2 region servers shutdown, I think DLR still > useful > >>> to bring regions online more quickly and with less IO usage. > >>> > >>> > >>> Regards > >>> Allan Yang > >>> > >>> > >>> > >>> > >>> > >>> > >>> At 2016-10-17 21:01:16, "Ted Yu" <[email protected]> wrote: > >>> >Here was the thread discussing DLR: > >>> > > >>> >http://search-hadoop.com/m/YGbbOxBK2n4ES12&subj=Re+ > >>> DISCUSS+retiring+current+DLR+code > >>> > > >>> >> On Oct 17, 2016, at 4:15 AM, allanwin <[email protected]> wrote: > >>> >> > >>> >> Hi, All > >>> >> DLR can improve MTTR dramatically, but since it have many bugs like > >>> HBASE-13567, HBASE-12743, HBASE-13535, HBASE-14729(any more I'don't > know?), > >>> it was proved unreliable, and has been deprecated almost in all > branches > >>> now. > >>> >> > >>> >> > >>> >> My question is, is there any other way other than DLR to improve > MTTR? > >>> 'Cause If a big cluster crashes, It takes a long time to bring regions > >>> online, not to mention it will create huge pressure on the IOs. > >>> >> > >>> >> > >>> >> To tell the truth, I still want DLR back, if the community don't > have > >>> any plan to bring back DLR, I may want to figure out the problems in > DLR > >>> and make it working and reliable, Any suggests for that? > >>> >> > >>> >> > >>> >> sincerely > >>> >> Allan Yang > >>> >
