OK, the original issue is HBCK2 for AMv2, but here we need to do more, not only for AMv2.
Let me open a new issue and post what Andrew said above there. 张铎(Duo Zhang) <palomino...@gmail.com> 于2019年1月19日周六 上午9:26写道： > OK, let me find the original HBCK2 issue and see how can we make progress > on it. > > BTW, on scan performance, Zheng Hu has done a work to get about 40% > performance back in this issue for 100% scan case on ycsb > > https://issues.apache.org/jira/browse/HBASE-21657 > > Andrew Purtell <apurt...@apache.org> 于2019年1月19日周六 上午8:14写道： > >> Lars was testing tip of branch-2 with Phoenix and said scans were 50% >> slower than branch-1. I’ll try and get him to provide more details. Anyway >> after hbck2 is complete issues like that will come out in the testing we’d >> do as part of sanity checking a move of the pointer. >> >> On Fri, Jan 18, 2019 at 4:02 PM Zach York <zyork.contribut...@gmail.com> >> wrote: >> >> > I agree with the sentiment around HBCK2. I think these kind of recovery >> > tools are essential before marking something stable. >> > >> > I also remember when we did testing around HBase 2.x/2.1 that we were >> > getting perf degradations and couldn't seem to get performance to be as >> > good as we were getting in the 1.x line. >> > >> > - Zach >> > >> > On Thu, Jan 17, 2019 at 11:06 PM Pankaj kr <pankaj...@huawei.com> >> wrote: >> > >> > > Yeah, HBCK2/ OfflineMetaRepair tools are really required to migrate >> old >> > > version data to HBase-2. We have use cases where we are using these >> tools >> > > to rebuild the meta for further region assignment. >> > > Similar discussion is going on HBASE-21665, after fixing the NPE and >> > > rebuilding the meta, master don't assign the regions as we skip the >> empty >> > > regions while loading meta during master startup. >> > > >> > > A big +1 from my side on this... >> > > >> > > Regards, >> > > Pankaj >> > > >> > > -----Original Message----- >> > > From: 张铎(Duo Zhang) [mailto:palomino...@gmail.com] >> > > Sent: 18 January 2019 11:55 >> > > To: HBase Dev List <dev@hbase.apache.org> >> > > Subject: Re: [DISCUSS] Moving towards a branch-2 line that can get the >> > > 'stable' pointer. >> > > >> > > So the first priority is to make progress on HBCK2? If we all agree, >> > let's >> > > start to work. >> > > >> > > Andrew Purtell <apurt...@apache.org> 于2019年1月18日周五 下午12:31写道： >> > > >> > > > Sorry, let me add... Check all the boxes on that list and I'm +1 for >> > > > moving the stable pointer (modulo some time to pound on the >> candidate >> > > > to really put it through its paces, like two weeks of chaos...) >> > > > >> > > > On Thu, Jan 17, 2019 at 8:28 PM Andrew Purtell <apurt...@apache.org >> > >> > > > wrote: >> > > > >> > > > > I do not believe we should move the stable pointer to any 2.x >> until >> > > > > HBCK2 is feature complete. We can discuss what that milestone >> should >> > > look like. >> > > > > At a minimum, I think we need: >> > > > > >> > > > > - Rebuild meta from region metadata in the filesystem, aka >> offline >> > > > > meta rebuild. >> > > > > - Fix assignment errors (undeployed regions, double assignments >> > > (yes, >> > > > > should not be possible), etc) >> > > > > - Fix region holes, overlaps, and other errors in the region >> chain >> > > > > - Fix failed split and merge transactions that have failed to >> roll >> > > > > back due to some bug (related to previous) >> > > > > - Enumerate store files to determine file level corruption and >> > > > > sideline corrupt files >> > > > > - Fix hfile link problems (dangling / broken) >> > > > > >> > > > > This is a list of the real problems I have had to fix in >> production >> > > > > at least once (in the past 10 years...). >> > > > > >> > > > > On Thu, Jan 17, 2019 at 8:19 PM 张铎(Duo Zhang) >> > > > > <palomino...@gmail.com> >> > > > > wrote: >> > > > > >> > > > >> There are still lots of small new features which we want to >> > > > >> integrate >> > > > into >> > > > >> branch-2 so I'm -1 on making release directly from branch-2. >> > > > >> Backporting at once before release is a pain I'd say, I've tried >> > > > >> this many times recently, as we have to follow up the community >> > > > >> version...Let's make a branch-2.2 when we want to release 2.2.0, >> > > > >> and maybe also retire the branch-2.0? >> > > > >> >> > > > >> For the stable pointer, I think 2.1.x maybe a good candidate? >> > > > >> Though we know that we may still have some bugs for the AMv2, but >> > > > >> actually we all know that the AMv1 for all the branch-1.x also >> has >> > > > >> lots of bugs, that's why hbck is very important. >> > > > >> >> > > > >> And also +! on making progress on HBCK2, we need to port he >> useful >> > > > >> features of HBCK1 to HBCK2. There is no software can guarantee >> that >> > > > >> there is no bug, so FWIW we should have a way to fix broken >> > > > >> clusters. >> > > > >> >> > > > >> Sean Busbey <bus...@apache.org> 于2019年1月18日周五 上午11:47写道： >> > > > >> >> > > > >> > There are a few related topics I'd like to discuss and I >> figured >> > > > >> > this subject line is the most likely to get a bit of attention. >> > > > >> > :) >> > > > >> > >> > > > >> > First, I'd like us all to get on the same page wrt the current >> > > > >> > state of branch-2. Personally, I don't think it can be released >> > > > >> > as-is with a 2.y version because folks can't rolling upgrade >> from >> > > > >> > 2.0 or 2.1 to it due to the current implementation of >> > > > >> > HBASE-20881. As Duo has mentioned a couple of times, folks have >> > > > >> > to ensure there are no region transitions around during the >> > > > >> > upgrade. I think that will be prohibitive for folks looking to >> > > upgrade. What do other folks think? >> > > > >> > >> > > > >> > Second, I think our recent discussions around the need for >> > > > >> > shifting to more minor releases for HBase 1.y also applies to >> the >> > > 2.y branches. >> > > > >> > branch-2 hasn't had a release since 2.1.0 came out in July >> 2018. >> > > > >> > That's a scary long amount of time. I think it contributes to >> us >> > > > >> > ending up with changes like the above since it's easy to think >> > > > >> > about the branch as something that has a lot of time before the >> > > > >> > next release. >> > > > >> > >> > > > >> > Personally, I'd like to see us skip making minor-release >> specific >> > > > >> > branches for a bit unless a CVE fix or something comes up. >> > > > >> > Ideally, that would mean we work towards a 2.2.0 release >> directly >> > > > >> > from branch-2 and then 2.2.1, etc. When we have a feature >> that's >> > > > >> > ready to backport from the master branch for a release we then >> > > > >> > update branch-2's version to be 2.3.0. >> > > > >> > >> > > > >> > Or maybe we try set a regular cadence to feature releases by >> > > > >> > having >> > > > >> > branch-2 release a new minor, two months of new maintenance >> > > > >> > releases, followed by a new minor. That would mean after the >> last >> > > > >> > of the maintenance releases we'd have a window of a few weeks >> > > > >> > where we can all decide which features in master are mature >> > > > >> > enough to backport for the new minor release. >> > > > >> > >> > > > >> > Lastly, what would it take for folks to feel confident moving >> the >> > > > >> > 'stable' pointer to a HBase 2.y? Is there a major gap still on >> > > > >> > assignment stability? Is it a more thorough look at >> performance? >> > > > >> > More time to ensure HBCK2 has good coverage of failure modes >> that >> > > need it? >> > > > >> > >> > > > >> >> > > > > >> > > > > >> > > > > -- >> > > > > Best regards, >> > > > > Andrew >> > > > > >> > > > > Words like orphans lost among the crosstalk, meaning torn from >> > > > > truth's decrepit hands >> > > > > - A23, Crosstalk >> > > > > >> > > > >> > > > >> > > > -- >> > > > Best regards, >> > > > Andrew >> > > > >> > > > Words like orphans lost among the crosstalk, meaning torn from >> truth's >> > > > decrepit hands >> > > > - A23, Crosstalk >> > > > >> > > >> > >> -- >> Best regards, >> Andrew >> >> Words like orphans lost among the crosstalk, meaning torn from truth's >> decrepit hands >> - A23, Crosstalk >> >
