On Wed, Jul 8, 2015 at 7:53 AM, Sean Busbey <[email protected]> wrote:
> Hi Folks! > > For the 1.2 release, I think the consensus is to disable Distributed Log > Replay by default due to lack of sufficient testing. At least, that's the > only feedback I've heard so far. :) > > Anyone object to that? > > I've been trying it over the last few days. It is easy enough to lose data: HBASE-14028. It is a bit tough tracing how the loss is happening given more moving parts and that it seems few have treaded this route previously; breadcrumbs are sparse (fixing). I'll keep at this until DLR in 1.2 is for sure a lost cause. On DLR: + DLR is a little more involved than DLS -- which is already tough enough to follow. It might be best to just punt and come back here after assign has been redone (and simplified) on top of pv2; hbase-2.0.0? + It can actually make for a worse MTTR as it does not do re-lookups during replay of a WAL if the target server crashes during DLR; the whole WAL replay must timeout before we'll go re-find the new location (30 seconds at least). St.Ack Presuming no one does,what do folks think about just disabling it by > default in the current branch-1? > > That isn't to say it couldn't switch to on-by-default at a latter 1.y > release. It's just that we had to turn it off right before the 1.1 releases > as well, and I'd prefer we avoid these last minute changes in favor of > waiting until someone has the time to prioritize thorough testing. > > > -- > Sean >
