The gc log file is best to share when asking for help with tuning. The top of file has all the computed args it ran with and it gives details on what part of the GC is taking time. I would guess the CPU spike is from full GCs which with that small heap of a heap is probably from evacuation failures. Reserving more of the heap to be free (-XX:G1ReservePercent=25) can help, along with increasing the amount of heap. 8GB is pretty small for G1, might be better off with CMS.
Chris > On Jun 13, 2018, at 8:42 AM, rajpal reddy <rajpalreddy...@gmail.com> wrote: > > Hello, > > we are using G1GC and noticing garbage collection taking a while and during > that process we are seeing cpu spiking up to 70-80%. can you please let us > know. if we have to tune any parameters for that. attaching the cassandra-env > file with jam-options.<cassandra-env.txt> > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > For additional commands, e-mail: user-h...@cassandra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org