That probably isnt enough data, so if youre interested: https://gofile.io/?c=rZQ2y4
On Thu, Dec 5, 2019 at 2:52 PM David Hastings <hastings.recurs...@gmail.com> wrote: > I know theres no hard answer, and I know the Xms and Xmx should be the > same, but it was a set it and forget it sort of thing from years ago. I > will definitely be changing it but figured I may as well figure out as > much as possible from this user group resource. > as far as the raw GC data goes: > https://pastebin.com/vBtpYR1W > > (i dont know if people still use pastebin) i can get more if needed. the > systems dont do ANY indexing at all, they are search only slaves. they > share resources only with a DB install, and one node will never do both > live search and live DB. If theres any more info youd like I would be > happy to provide, this is interesting. > > On Thu, Dec 5, 2019 at 2:41 PM Shawn Heisey <apa...@elyograg.org> wrote: > >> On 12/5/2019 11:58 AM, David Hastings wrote: >> > as of now we do an xms of 8gb and xmx of 60gb, generally through the >> > dashboard the JVM hangs around 16gb. I know Xms and Xmx are supposed >> to be >> > the same so thats the change #1 on my end, I am just concerned of >> dropping >> > it from 60 as thus far over the last few years I have had no problems >> nor >> > performance issues. I know its said a lot of times to make it lower and >> > let the OS use the ram for caching the file system/index files, so my >> first >> > experiment was going to be around 20gb, was wondering if this seems >> sound, >> > or should i go even lower? >> >> The Xms and Xmx settings should be the same so Java doesn't need to take >> special action to increase the pool size when more than the minimum is >> required. Java tends to always increase to the maximum as it runs, so >> there's usually little benefit to specifying a lower minimum than the >> maximum. With a 60GB max heap, Java is likely to grab a little more >> than 60GB from the OS, regardless of how much heap is actually in use. >> >> If you can provide GC logs from Solr that cover a signficant timeframe, >> especially heavy indexing, we can analyze those and make an estimate >> about the values you should have for Xms and Xmx. It will only be a >> guess ... something might happen later that requires more heap. >> >> We can't make recommendations without hard data. The information you >> provided isn't enough to guess how much heap you'll need. Depending on >> how such a system is used, a few GB might be enough, or you might need a >> lot more. >> >> >> https://lucidworks.com/post/sizing-hardware-in-the-abstract-why-we-dont-have-a-definitive-answer/ >> >> Thanks, >> Shawn >> >
