There are no bad GCs in the gclog (worse is like 100ms). Everything looks great actually from what I see. CPU utilization isn't inherently a bad thing for what its worth.
Chris > On Jun 14, 2018, at 1:18 PM, rajpal reddy <rajpalreddy...@gmail.com> wrote: > > Hey Chris, > > Sorry to bother you. Did you get a chance to look at the gclog file I sent > last night. > > On Wed, Jun 13, 2018, 8:44 PM rajpal reddy <rajpalreddy...@gmail.com > <mailto:rajpalreddy...@gmail.com>> wrote: > Chris, > > sorry attached wrong log file. attaching gc collection seconds and cpu. there > were going high at the same time and also attached the gc.log. grafana > dashboard and gc.log timing are 4hours apart gc can be see 06/12th around > 22:50 > > rate(jvm_gc_collection_seconds_sum{"}[5m]) > > > On Jun 13, 2018, at 5:26 PM, Chris Lohfink <clohf...@apple.com > > <mailto:clohf...@apple.com>> wrote: > > > > There are not even a 100ms GC pause in that, are you certain theres a > > problem? > > > >> On Jun 13, 2018, at 3:00 PM, rajpal reddy <rajpalreddy...@gmail.com > >> <mailto:rajpalreddy...@gmail.com>> wrote: > >> > >> Thanks Chris I did attached the gc logs already. reattaching them > >> now<gc.log.1.current>. > >> > >> it started yesterday around 11:54PM > >>> On Jun 13, 2018, at 3:56 PM, Chris Lohfink <clohf...@apple.com > >>> <mailto:clohf...@apple.com>> wrote: > >>> > >>>> What is the criteria for picking up the value for G1ReservePercent? > >>> > >>> > >>> it depends on the object allocation rate vs the size of the heap. > >>> Cassandra ideally would be sub 500-600mb/s allocations but it can spike > >>> pretty high with something like reading a wide partition or repair > >>> streaming which might exceed what the g1 ygcs tenuring and timing is > >>> prepared for from previous steady rate. Giving it a bigger buffer is a > >>> nice safety net for allocation spikes. > >>> > >>>> is the HEAP_NEWSIZE is required only for CMS > >>> > >>> > >>> it should only set Xmn with that if using CMS, with G1 it should be > >>> ignored or else yes it would be bad to set Xmn. Giving the gc logs will > >>> give the results of all the bash scripts along with details of whats > >>> happening so its your best option if you want help to share that. > >>> > >>> Chris > >>> > >>>> On Jun 13, 2018, at 12:17 PM, Subroto Barua > >>>> <sbarua...@yahoo.com.INVALID> wrote: > >>>> > >>>> Chris, > >>>> What is the criteria for picking up the value for G1ReservePercent? > >>>> > >>>> Subroto > >>>> > >>>>> On Jun 13, 2018, at 6:52 AM, Chris Lohfink <clohf...@apple.com > >>>>> <mailto:clohf...@apple.com>> wrote: > >>>>> > >>>>> G1ReservePercent > >>>> > >>>> --------------------------------------------------------------------- > >>>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > >>>> <mailto:user-unsubscr...@cassandra.apache.org> > >>>> For additional commands, e-mail: user-h...@cassandra.apache.org > >>>> <mailto:user-h...@cassandra.apache.org> > >>>> > >>> > >>> > >>> --------------------------------------------------------------------- > >>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > >>> <mailto:user-unsubscr...@cassandra.apache.org> > >>> For additional commands, e-mail: user-h...@cassandra.apache.org > >>> <mailto:user-h...@cassandra.apache.org> > >>> > >> > >> > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > >> <mailto:user-unsubscr...@cassandra.apache.org> > >> For additional commands, e-mail: user-h...@cassandra.apache.org > >> <mailto:user-h...@cassandra.apache.org> > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > > <mailto:user-unsubscr...@cassandra.apache.org> > > For additional commands, e-mail: user-h...@cassandra.apache.org > > <mailto:user-h...@cassandra.apache.org> > > >
