walog provides data loss protection in a specific set of circumstances. Most of our deployments are under a different set of circumstances. Accumulo is only one part of our systems and we have other mechanisms for protecting against the loss of data. We find the walog actually becomes a bottleneck in certain circumstances and so turning it off increases the overall reliability of our system.
On Sat, May 17, 2014 at 04:27:29PM -0400, Josh Elser wrote: > You're likely to lose data in *any* deployment with the walogs turned off. > > And, to reiterate what Sean says, I wouldn't really consider any > benchmark with the walogs turned off valid except for "internal" > benchmarks (ones where we evaluate components only within Accumulo > for the sake of improving Accumulo itself and not comparing it to > other systems). > > On 5/17/14, 3:30 PM, Sean Busbey wrote: > >You can set both of those in the accumulo-site.xml. > > > >However, it's going to be difficult to use benchmarks with walogs > >disabled for valid comparisons to other systems. Also you are very > >likely to lose data in any significantly sized deployment. > > > > > > > >On Sat, May 17, 2014 at 1:35 PM, Kepner, Jeremy - 0553 - MITLL > ><[email protected] <mailto:[email protected]>> wrote: > > > > As part of our Accumulo benchmarking we have decided to set certain > > values as defaults for all our databases: > > > > tserver.compaction.minor.concurrent.max=5 > > table.walog.enabled=false > > > > We were wondering which file(s) we would need to modify to apply > > these defaults? > > > > > > > > > >-- > >Sean
