Kojo: On the surface, this is a reasonable configuration. Note that you may still want to decrease the Java heap, but only if you have enough “head room” for memory spikes.
How do you know if you have “head room”? Unfortunately the only good answer is “you have to test”. You can look at the GC logs to see what your maximum heap requirements are, then add “some extra”. Note that there’s a balance here. Let’s say you can run successfully with X heap, so you allocate X + 0.1X to the heap. You can wind up spending a large amount of time in garbage collection. I.e. GC kicks in and recovers _just_ enough memory to continue for a very short while, then goes into another GC cycle. You don’t hit OOMs, but your system is slow. OTOH, let’s say you need X and allocate 3X. Garbage will accumulate and full GCs are rarer, but when they occur they take longer. And the G1GC collector is the current preference As I said, testing is really the only way to determine what the magic number is. Best, Erick > On Aug 14, 2019, at 9:20 AM, Kojo <rbsnk...@gmail.com> wrote: > > Shawn, > > Only my web application access this solr. at a first look at http server > logs I didnt find something different. Sometimes I have a very big crawler > access to my servers, this was my first bet. > > No scheduled crons running at this time too. > > I think that I will reconfigure my boxes with two solr nodes each instead > of four and increase heap to 16GB. This box only run Solr and has 64Gb. > Each Solr will use 16Gb and the box will still have 32Gb for the OS. What > do you think? > > This is a production server, so I will plan to migrate. > > Regards, > Koji > > > Em ter, 13 de ago de 2019 às 12:58, Shawn Heisey <apa...@elyograg.org> > escreveu: > >> On 8/13/2019 9:28 AM, Kojo wrote: >>> Here are the last two gc logs: >>> >>> >> https://send.firefox.com/download/6cc902670aa6f7dd/#Ee568G9vUtyK5zr-nAJoMQ >> >> Thank you for that. >> >> Analyzing the 20MB gc log actually looks like a pretty healthy system. >> That log covers 58 hours of runtime, and everything looks very good to me. >> >> https://www.dropbox.com/s/yu1pyve1bu9maun/gc-analysis-kojo.png?dl=0 >> >> But the small log shows a different story. That log only covers a >> little more than four minutes. >> >> https://www.dropbox.com/s/vkxfoihh12brbnr/gc-analysis-kojo2.png?dl=0 >> >> What happened at approximately 10:55:15 PM on the day that the smaller >> log was produced? Whatever happened caused Solr's heap usage to >> skyrocket and require more than 6GB. >> >> Thanks, >> Shawn >>
