Hi guys, Can someone confirm if it is true that dynamic allocation on mesos "is designed to run one executor per slave with the configured amount of resources." I copied this sentence from the documentation. Does this mean there is at most 1 executor per node? Therefore, if you have a big machine, you need to allocate a fat executor on this machine in order to fully utilize it?
Best Regards, Sent from my iPhone > On 23 Nov, 2015, at 8:36 am, Iulian Dragoș <iulian.dra...@typesafe.com> wrote: > > > >> On Sat, Nov 21, 2015 at 3:37 AM, Adam McElwee <a...@mcelwee.me> wrote: >> I've used fine-grained mode on our mesos spark clusters until this week, >> mostly because it was the default. I started trying coarse-grained because >> of the recent chatter on the mailing list about wanting to move the mesos >> execution path to coarse-grained only. The odd things is, coarse-grained vs >> fine-grained seems to yield drastic cluster utilization metrics for any of >> our jobs that I've tried out this week. >> >> If this is best as a new thread, please let me know, and I'll try not to >> derail this conversation. Otherwise, details below: > > I think it's ok to discuss it here. > >> We monitor our spark clusters with ganglia, and historically, we maintain at >> least 90% cpu utilization across the cluster. Making a single configuration >> change to use coarse-grained execution instead of fine-grained consistently >> yields a cpu utilization pattern that starts around 90% at the beginning of >> the job, and then it slowly decreases over the next 1-1.5 hours to level out >> around 65% cpu utilization on the cluster. Does anyone have a clue why I'd >> be seeing such a negative effect of switching to coarse-grained mode? GC >> activity is comparable in both cases. I've tried 1.5.2, as well as the 1.6.0 >> preview tag that's on github. > > I'm not very familiar with Ganglia, and how it computes utilization. But one > thing comes to mind: did you enable dynamic allocation on coarse-grained mode? > > iulian
