Why do you believe you need such a huge heap as 31g? Can you support such a choice by some observations or measurements?
Jan > 14. mar. 2023 kl. 06:39 skrev HariBabu kuruva <hari2708.kur...@gmail.com>: > > Thank you all for your responses. > > There are no spaces between Xms and the values. > > I have updated similar arguments(-Xms30720m -Xmx30720m) in one of the > non-prod environments(in mbs instead of gb). It correctly shows the max > heap as 30GB in the Solr UI. > > So, I would like to update 31.5 GB similarly in PROD (-Xms32256m > -Xmx32256m). Before applying that should i analyze heap memory stats using > Heap analyzer tool or i can go ahead and apply. I have a total server > memory of 62GB and only solr is running in it. Please suggest. > > > On Thu, Mar 9, 2023 at 8:00 PM Walter Underwood <wun...@wunderwood.org> > wrote: > >> Use a heap analysis tool. You’ll see a sawtooth pattern in the heap size. >> The bottom of that sawtooth is the actual amount of memory that Solr is >> using. Pick the highest point of the bottom of the sawtooth, then add some >> headroom, maybe a gigabyte. Test with that value. >> >> wunder >> Walter Underwood >> wun...@wunderwood.org >> https://observer.wunderwood.org/ (my blog) >> >>> On Mar 9, 2023, at 5:23 AM, Dave <hastings.recurs...@gmail.com> wrote: >>> >>> Agreed, but often times as a developer you are subject to the requests >> of those higher up and you end up with 30 facets of strings that are the >> length of names. But yes, test as low as you can and try to keep the >> qtimes low and just keep adjusting until you are happy with whatever time >> works for you, I preferred sub half second but the index was 400+ gb so I >> used a large heap >>> >>>> On Mar 9, 2023, at 7:56 AM, Jan Høydahl <jan....@cominvent.com> wrote: >>>> >>>> It's a waste to set heap to 30g if your use of Solr only requires 6g >> to function. That is 24G memory not being used for index caching, and it >> will may, depending on chose GC, cause bigger/longer GC events as more >> garbage piles up before collection. >>>> >>>> You have to measure and experiment to find your heap sweetspot. >>>> It is a common misconception that giving more heap to Solr improves >> performance of something, it's rather the contrary. Only rarely do you need >> huge internal solr caches, and if you find yourself needing that kind of >> memory due to requesting huge number of docs or faceting on high >> cardinality long string fields or whatever, then it is better to optimize >> your use of Solr to lower the footprint than to add >30g. >>>> >>>> Jan >>>> >>>>> 9. mar. 2023 kl. 12:52 skrev Dave <hastings.recurs...@gmail.com>: >>>>> >>>>> Again, set to less than 32, I liked 30 >>>>> >>>>>>> On Mar 9, 2023, at 1:04 AM, Deepak Goel <deic...@gmail.com> wrote: >>>>>> >>>>>> The max heap could be the max heap used by the process uptill now. >> And not >>>>>> the max value you have set. I would suggest you increase the load by >> at >>>>>> least 20 times to see the max heap to go to 32 gb. >>>>>> >>>>>> >>>>>> Deepak >>>>>> "The greatness of a nation can be judged by the way its animals are >> treated >>>>>> - Mahatma Gandhi" >>>>>> >>>>>> +91 73500 12833 >>>>>> deic...@gmail.com >>>>>> >>>>>> Facebook: https://www.facebook.com/deicool >>>>>> LinkedIn: www.linkedin.com/in/deicool >>>>>> >>>>>> "Plant a Tree, Go Green" >>>>>> >>>>>> Make In India : http://www.makeinindia.com/home >>>>>> >>>>>> >>>>>>> On Thu, Mar 9, 2023 at 8:21 AM Shawn Heisey <apa...@elyograg.org> >> wrote: >>>>>>> >>>>>>>> On 3/8/2023 9:24 AM, HariBabu kuruva wrote: >>>>>>>> I have set the Heap memory as -Xms 1g -Xmx 40g in the Production >>>>>>>> environment. >>>>>>>> >>>>>>>> But when i see the Heap memory in the Solr UI. I can see the Max >> Heap >>>>>>> below. >>>>>>>> >>>>>>>> Max: 3.8Gb >>>>>>>> Used: 2.2Gb >>>>>>> >>>>>>> The other answers you've gotten are good. This is mostly just a >> little >>>>>>> more detail. >>>>>>> >>>>>>> If you really do have the spaces before the 1g and 40g, then those >>>>>>> values are probably not being honored as Jan said. >>>>>>> >>>>>>> If you don't have the spaces, then Java will start with the heap >> size at >>>>>>> 1GB, and only increase it if there is enough memory pressure. One >> thing >>>>>>> that I don't know is whether Java will use the 32 bit pointers with >> the >>>>>>> Xmx at 40g. It probably won't, so I expect that memory usage would >> be >>>>>>> more efficient if you set the max heap to 31g. >>>>>>> >>>>>>> With a heap size at 32GB or larger, Java has to use 64 bit pointers, >> and >>>>>>> that will make it use quite a bit more memory because Solr creates a >> LOT >>>>>>> of objects. >>>>>>> >>>>>>> As Dave said, if you use Xms and Xmx, then they should be set to the >>>>>>> same value. And the value should be less than 32GB for efficiency. >>>>>>> >>>>>>> If you use the SOLR_HEAP environment variable in the include script, >>>>>>> then both Xms and Xmx will be set to the provided value. >>>>>>> >>>>>>> Thanks, >>>>>>> Shawn >>>>>>> >>>> >> >> > > -- > > Thanks and Regards, > Hari > Mobile:9790756568
