You can also use -Xmn with that gc to size the new gen such that those buffers don't get tenured
I don't think that's an option with G1 On Wednesday, October 14, 2015, Cory Kolbeck <ckolb...@gmail.com> wrote: > I'm not sure that will help here, you'll likely have the same > medium-lifetime buffers getting into the tenured generation and forcing > large collections. > > On Wed, Oct 14, 2015 at 10:00 AM, Gerrit Jansen van Vuuren < > gerrit...@gmail.com <javascript:;>> wrote: > > > Hi, > > > > I've seen pauses using G1 in other applications and have found that > > -XX:+UseParallelGC > > -XX:+UseParallelOldGC works best if you're having GC issues in general > on > > the JVM. > > > > > > Regards, > > Gerrit > > > > On Wed, Oct 14, 2015 at 4:28 PM, Cory Kolbeck <ckolb...@gmail.com > <javascript:;>> wrote: > > > > > Hi folks, > > > > > > I'm a bit new to the operational side of G1, but pretty familiar with > its > > > basic concept. We recently set up a Kafka cluster to support a new > > product, > > > and are seeing some suboptimal GC performance. We're using the > parameters > > > suggested in the docs, except for having switched to java 1.8_40 in > order > > > to get better memory debugging. Even though the cluster is handling > only > > > 2-3k messages per second per node, we see periodic 11-18 second > > > stop-the-world pauses on a roughly hourly cadence. I've turned on > > > additional GC logging, and see no humongous allocations, it all seems > to > > be > > > buffers making it into the tenured gen. They appear to be collectable, > as > > > the collection triggered by dumping the heap collects them all. Ideas > for > > > additional diagnosis or tuning very welcome. > > > > > > --Cory > > > > > >