Erick, Thanks for your reply.
Yes, "virtual memory" does not mean physical memory. But if when "virtual memory" >> physical memory, the system will change to slow, since lots for paging request happen. Yongtao -----Original Message----- From: Erick Erickson [mailto:erickerick...@gmail.com] Sent: Tuesday, November 15, 2011 8:37 AM To: solr-user@lucene.apache.org Subject: Re: memory usage keep increase I'm pretty sure not. The words "virtual memory address space" is important here, that's not physical memory... Best Erick On Mon, Nov 14, 2011 at 11:55 AM, Yongtao Liu <y...@commvault.com> wrote: > Hi all, > > I saw one issue is ram usage keep increase when we run query. > After look in the code, looks like Lucene use MMapDirectory to map index file > to ram. > > According to > http://lucene.apache.org/java/3_1_0/api/core/org/apache/lucene/store/MMapDirectory.html > comments, it will use lot of memory. > NOTE: memory mapping uses up a portion of the virtual memory address space in > your process equal to the size of the file being mapped. Before using this > class, be sure your have plenty of virtual address space, e.g. by using a 64 > bit JRE, or a 32 bit JRE with indexes that are guaranteed to fit within the > address space. > > So, my understanding is solr request physical RAM >= index file size, is it > right? > > Yongtao > > > ******************Legal Disclaimer*************************** > "This communication may contain confidential and privileged material > for the sole use of the intended recipient. Any unauthorized review, > use or distribution by others is strictly prohibited. If you have > received the message in error, please advise the sender by reply email > and delete the message. Thank you." > *********************************************************
