Hi Mingyu, Maybe we should be limiting our heaps to 32GB max and running multiple workers per machine to avoid large GC issues.
For a 128GB memory, 32 core machine, this could look like: SPARK_WORKER_INSTANCES=4 SPARK_WORKER_MEMORY=32 SPARK_WORKER_CORES=8 Are people running with large (32GB+) executor heaps in production? I'd be curious to hear if so. Cheers! Andrew On Thu, Oct 2, 2014 at 1:30 PM, Mingyu Kim <m...@palantir.com> wrote: > This issue definitely needs more investigation, but I just wanted to > quickly check if anyone has run into this problem or has general guidance > around it. We’ve seen a performance degradation with a large heap on a > simple map task (I.e. No shuffle). We’ve seen the slowness starting around > from 50GB heap. (I.e. spark.executor.memoty=50g) And, when we checked the > CPU usage, there were just a lot of GCs going on. > > Has anyone seen a similar problem? > > Thanks, > Mingyu >