>I think there is no benefit in having multiple Solr instances on a single >server, unless the heap memory required by the JVM is too big. ****Deepak*** I would try multiple Solr instances rather a single Solr instance (it definitely will give a performance boost) ****Deepak*** >And remember that this has relatively to do with the index size ( inverted >index is memory mapped OFF heap and docValues as well). >On the other hand of course Apache Solr uses plenty of JVM heap memory as >well ( caches, temporary data structures during indexing, ect ect)
> Deepak: > > Well its kinda a given that when running ANYTHING under a VM you have an > overhead.. >***Deepak*** >You mean you are assuming without any facts (performance benchmark with n >without VM) >***Deepak*** >I think Shawn detailed this quite extensively, I am no sys admin or OS >expert, but there is no need of benchmarks and I don't even understand your >doubts. >In Information technology anytime you add additional layers of software you >need adapters which means additional instructions executed. >It is obvious that having : >metal -> OS -> APP is cheaper instruction wise then >metal -> OS -> VM -> APP >The APP will execute instruction in the VM that will be responsible to >translate those instructions for the underlining OS. ****Deepak*** I had past experience with VM's. They absolutely do not take any overheads. Since we have conflicting opinions, it is best to benchmark it yourself ****Deepak*** >Going direct you skip one passage. >you can think about this when you emulate different OS, is it cheaper to run >windows on a machine directly to execute windows applications or run a >Windows VM on top of another OS to execute windows applications ? Deepak "Please stop cruelty to Animals, help by becoming a Vegan" +91 73500 12833 deic...@gmail.com Facebook: https://www.facebook.com/deicool LinkedIn: www.linkedin.com/in/deicool "Plant a Tree, Go Green" On Thu, Mar 15, 2018 at 9:43 PM, Alessandro Benedetti <a.benede...@sease.io> wrote: > *Single Solr Instance VS Multiple Solr instances on Single Server > * > > I think there is no benefit in having multiple Solr instances on a single > server, unless the heap memory required by the JVM is too big. > And remember that this has relatively to do with the index size ( inverted > index is memory mapped OFF heap and docValues as well). > On the other hand of course Apache Solr uses plenty of JVM heap memory as > well ( caches, temporary data structures during indexing, ect ect) > > > Deepak: > > > > Well its kinda a given that when running ANYTHING under a VM you have an > > overhead.. > > ***Deepak*** > You mean you are assuming without any facts (performance benchmark with n > without VM) > ***Deepak*** > I think Shawn detailed this quite extensively, I am no sys admin or OS > expert, but there is no need of benchmarks and I don't even understand your > doubts. > In Information technology anytime you add additional layers of software you > need adapters which means additional instructions executed. > It is obvious that having : > metal -> OS -> APP is cheaper instruction wise then > metal -> OS -> VM -> APP > The APP will execute instruction in the VM that will be responsible to > translate those instructions for the underlining OS. > Going direct you skip one passage. > you can think about this when you emulate different OS, is it cheaper to > run > windows on a machine directly to execute windows applications or run a > Windows VM on top of another OS to execute windows applications ? > > > > ----- > --------------- > Alessandro Benedetti > Search Consultant, R&D Software Engineer, Director > Sease Ltd. - www.sease.io > -- > Sent from: http://lucene.472066.n3.nabble.com/Solr-User-f472068.html >
