From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: looking for explanations on linux memory management From: Rob Love In-Reply-To: <200311261830.02711.mickael.bailly@telintrans.fr> References: <200311261830.02711.mickael.bailly@telintrans.fr> Content-Type: text/plain Message-Id: <1069870409.10070.8.camel@localhost> Mime-Version: 1.0 Date: Wed, 26 Nov 2003 13:13:29 -0500 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Mickael Bailly Cc: linux-mm@kvack.org List-ID: On Wed, 2003-11-26 at 12:30, Mickael Bailly wrote: > 1/ can you explain me what happened in week 47 so cached memory don't get down > anymore ? Nothing really changed in this week on the server. Somehow you started generating more page I/O and thus more page cache. What actually strikes me as odd is the fact it was so low despite having free memory. But it could be a low vs. high memory thing, since you have 2GB of RAM. The full output from /proc/meminfo and /proc/slabinfo might be more useful than this graph. > 2/ how can I know when my server needs more RAM/SWAP, if free memory is always > about 0 When swap is abnormally large (or, even better, when swapped activity is high. See vmstat(8)). Free memory being zero does not say much... Linux will use most of available memory for cache, but will of course prune that in response to page allocation. > 3/ can you tell me where to find PER PROCESS memory usage (/proc/[process > id]/stat ? /proc/[process id]/statm ? ) /proc/pid/status has VmSize, etc. You can also see this with ps(1) and top(1), of course. Rob Love -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org