I’ve found that each solr instance will take as many cores as it needs per request. Your 2 sec response sounds like you just started the server and then did that search. I never trust the first search as nothing has been put into memory yet. I like to give my jvms 31 gb each and let Linux cache the rest of the files as it sees fit, with swap turned completely off. Also *:* can be heavier than you think if you have every field indexed since it’s like a punch card like system where all the fields have to match.
> On Mar 18, 2022, at 12:45 PM, Vincenzo D'Amore <v.dam...@gmail.com> wrote: > > Thanks for your support, just sharing what I found until now. > > I'm working with SolrCloud with a 2 node deployment. This deployment has > many indexes but a main one 160GB index that has become very slow. > Select *:* rows=1 take 2 seconds. > SolrCloud instances are running in kubernetes and are deployed in a pod > with 128GB RAM but only 16GB to JVM. > Looking at Solr Documentation I've found nothing specific about what > happens to the performance if the number of CPUs is not correctly detected. > The only interesting page is the following and it seems to match with your > suggestion. > At the end of paragraph there is a not very clear reference about how the > Concurrent Merge Scheduler behavior can be impacted by the number of > detected CPUs. > >> Similarly, the system property lucene.cms.override_core_count can be set > to the number of CPU cores to override the auto-detected processor count. > >> Talking Solr to Production > Dynamic Defaults for ConcurrentMergeScheduler >> > https://solr.apache.org/guide/8_3/taking-solr-to-production.html#dynamic-defaults-for-concurrentmergescheduler > > > >> On Thu, Mar 17, 2022 at 1:22 PM Thomas Matthijs <li...@selckin.be> wrote: >> >> I don't know how it affects solr, but if you're interested in java's >> support to detect cgroup/container limits on cpu/memory etc, you can use >> these links as starting points to investigate. >> It affect some jvm configuration, like initial GC selection & settings >> that can affect performance. >> It was only backported to java 8 quite recently, so if you're still on >> that might want to check if you're on the latest version. >> >> https://bugs.java.com/bugdatabase/view_bug.do?bug_id=JDK-8146115 >> https://bugs.openjdk.java.net/browse/JDK-8264136 >> >> >>> On Thu, Mar 17, 2022, at 01:11, Vincenzo D'Amore wrote: >>> Hi Shawn, thanks for your help. >>> >>> Given that I’ll put the question in another way. >>> If Java don’t correctly detect the number of CPU how the overall >>> performance can be affected by this? >>> >>> Ciao, >>> Vincenzo >>> >>> -- >>> mobile: 3498513251 >>> skype: free.dev >>> >>>> On 16 Mar 2022, at 18:56, Shawn Heisey <elyog...@elyograg.org> wrote: >>>> >>>> On 3/16/22 03:56, Vincenzo D'Amore wrote: >>>>> just asking how can I rely on the number of processors the solr >> dashboard >>>>> shows. >>>>> >>>>> Just to give you a context, I have a 2 nodes solrcloud instance >> running in >>>>> kubernetes. >>>>> Looking at solr dashboard (8.3.0) I see there is only 1 cpu available >> per >>>>> solr instance. >>>>> but the Solr pods are deployed in two different kube nodes, and >> entering >>>>> the pod with the >>>>> kubectl exec -ti solr-0 -- /bin/bash >>>>> and running top I see there are 16 cores available for each solr >> instance. >>>> >>>> The dashboard info comes from Java, and Java gets it from the OS. How >> that works with containers is something I don't know much about. Here's >> what Linux says about a server I have which has two six-core Intel CPUs >> with hyperthreading. This is bare metal, not a VM or container: >>>> >>>> elyograg@smeagol:~$ grep processor /proc/cpuinfo >>>> processor : 0 >>>> processor : 1 >>>> processor : 2 >>>> processor : 3 >>>> processor : 4 >>>> processor : 5 >>>> processor : 6 >>>> processor : 7 >>>> processor : 8 >>>> processor : 9 >>>> processor : 10 >>>> processor : 11 >>>> processor : 12 >>>> processor : 13 >>>> processor : 14 >>>> processor : 15 >>>> processor : 16 >>>> processor : 17 >>>> processor : 18 >>>> processor : 19 >>>> processor : 20 >>>> processor : 21 >>>> processor : 22 >>>> processor : 23 >>>> >>>> If I start Solr on that server, the dashboard reports 24 processors. >>>> >>>> Thanks, >>>> Shawn >>>> >> > > > -- > Vincenzo D'Amore
