The actual limitation in Java is compressed pointers: http://docs.oracle.com/javase/7/docs/technotes/guides/vm/performance-enhancements-7.html#compressedOop
Thankfully Elasticsearch can run multiple nodes on the same server. Just pay attention to the direct size (off heap memory), mlockall settings and Lucene merge settings, as well as the allocation property referenced by David. Elasticsearch scales quite nicely vertically, so I would explore that option if possible. Cheers, Ivan On Wed, Sep 3, 2014 at 9:40 AM, vineeth mohan <[email protected]> wrote: > Hi , > > I am not sure if there is anything related to ES that makes a high RAM > problematic , but in general very high memory is not advised in java > systems. One of the reasons being the cobra effect which stems from the > fact that garbage collection might need more time for higher memory. > > COBRA EFFECT - > https://plumbr.eu/blog/increasing-heap-size-beware-of-the-cobra-effect > > Thanks > Vineeth > > > On Wed, Sep 3, 2014 at 10:04 PM, Jinyuan Zhou <[email protected]> > wrote: > >> I read somewhere that the ES_HEAP_SIZE is best to be less than 31G, in >> this case JVM can use an 32 bit number to address memory locations. If >> my server have about 64G ram. This seems a perfect. But what If I have a >> server with 128G RAM and sufficient CPU's. Which configuration is better >> a) two nodes on server each with ES_HEAP_SIZE say about 31G. b) one node >> on the server with ES_HEAP_SIZE say 64G. >> Thanks, >> >> -- >> You received this message because you are subscribed to the Google Groups >> "elasticsearch" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/elasticsearch/03180561-2e7d-4e04-ab97-9d8b3a922f86%40googlegroups.com >> <https://groups.google.com/d/msgid/elasticsearch/03180561-2e7d-4e04-ab97-9d8b3a922f86%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "elasticsearch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elasticsearch/CAGdPd5noOXMuVBZLoz9dJjxko5z4LmWBdk6aSTY2W2sUW7MbuA%40mail.gmail.com > <https://groups.google.com/d/msgid/elasticsearch/CAGdPd5noOXMuVBZLoz9dJjxko5z4LmWBdk6aSTY2W2sUW7MbuA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CALY%3DcQCF25cqzkhZ%2B2ooPfjFMyiSonWdKN%2BfPaiJvkEimK7Y0Q%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
