Was that back when forceSync was broken? ;-) (seriously) Patrick
On Fri, Jun 15, 2012 at 3:27 PM, Mahadev Konar <[email protected]> wrote: > Raj, > Are you seeing any perf improvements by using that setting? I had run > some benchmarks and didnt find much improvement even if I did > forceSync = no. > > thanks > mahadev > > On Fri, Jun 15, 2012 at 12:45 PM, Raj N <[email protected]> wrote: >> Thanks Patrick. So back to my original question. Will forceSync=no cause a >> zookeeper node to not start up cleanly if it crashed? It doesn't happen all >> the time. But it happened to me once. I had to cleanup all the transaction >> logs on all the nodes and then bring the nodes back up. For my use case I >> can tolerate losing data in the worst case scenario since I can regenerate >> all the data. But I should be able to tolerate a single point of failure as >> long as the node comes back up cleanly. Can zookeeper recover from a >> corrupt transaction log using existing snapshots and then replaying >> messages from its peers? >> >> Thanks >> -Raj >> >> On Fri, Jun 15, 2012 at 2:17 PM, Patrick Hunt <[email protected]> wrote: >> >>> For a single node failure I believe so. >>> >>> Patrick >>> >>> On Thu, Jun 14, 2012 at 11:56 AM, Raj N <[email protected]> wrote: >>> > Sorry, I should have been more specific. By corrupt, I mean that the >>> > zookeeper node doesn't come back up on a restart. I would have imagined >>> > that zookeeper would sync the lost transactions from its peers. I agree I >>> > will have a problem if I have multiple failures. But for a single node >>> > failure in a 3-node ensemble, I should be able to recover even if >>> > forceSync=no. >>> > >>> > Thanks >>> > -Raj >>> > >>> > On Thu, Jun 14, 2012 at 1:03 PM, Jonathan Simms <[email protected]> >>> wrote: >>> > >>> >> There's a big warning in the documentation that says that's a >>> possibility. >>> >> If you don't force both Java and the OS to flush their IO buffers to >>> disk, >>> >> then you have no guarantees that your data is consistent. >>> >> >>> >> On 6/14/12 10:56 AM, "Raj N" <[email protected]> wrote: >>> >> >>> >> >Are you guys aware of any issues with forceSync=no that could cause the >>> >> >transaction log to get corrupted on a zookeeper crash. >>> >> > >>> >> >Thanks >>> >> >-Raj >>> >> >>> >> >>> >> >>>
