Thanks Jay , I was trying to compute the *OS RAM requirement* *not JVM RAM* for a 14 GB Index [cumulative Index size of all Instances].And I put it thus -
Requirement of Operating System RAM for an Index of 14GB is - Index Size + 3 Times the maximum Index Size of Individual Instance for Optimize . That is to say ,I have several Instances ,combined Index Size is 14GB .Maximum Individual Index Size is 2.5GB .so My requirement for OS RAM is 14GB +3 * 2.5 GB ~ = 22GB. Correct? Regards Sujatha On Thu, Oct 20, 2011 at 3:45 AM, Jaeger, Jay - DOT <jay.jae...@dot.wi.gov>wrote: > Commit does not particularly spike disk or memory usage, unless you are > adding a very large number of documents between commits. A commit can cause > a need to merge indexes, which can increase disk space temporarily. An > optimize is *likely* to merge indexes, which will usually increase disk > space temporarily. > > How much disk space depends very much upon how big your index is in the > first place. A 2 to 3 times factor of the sum of your peak index file size > seems safe, to me. > > Solr uses only modest amounts of memory for the JVM for this stuff. > > JRJ > > -----Original Message----- > From: Sujatha Arun [mailto:suja.a...@gmail.com] > Sent: Wednesday, October 19, 2011 4:04 AM > To: solr-user@lucene.apache.org > Subject: Optimization /Commit memory > > Do we require 2 or 3 Times OS RAM memory or Hard Disk Space while > performing Commit or Optimize or Both? > > what is the requirement in terms of size of RAM and HD for commit and > Optimize > > Regards > Sujatha >