Hi Alexander, --- Alexander Burnos <alex@xxxxxxxxxxxxxxxx> escreveu: > Hello! > > On Mon, Sep 11, 2006 at 01:59:09PM +0000, Anand H. Krishnan wrote: > > >> straight out of the head, 50% memory free means about a GB. Is > your > > >system > > >> compiled with High Memory Support. If not, you can probably try > that. > > > > > >AFAIK High Memory Support is for >4GB of RAM. Moreover there is a > little > > > > No, no. HighMem is for > 1GB phys memory. You probably are talking > about > > PAE ? > > Yes, you're right. I was talking about PAE, anyway it isn't that case > as > I understand. > > > >bit another situation. When I have 600-1000Mb of RAM free, real > memory > > >that is used by applications is something near 1000-1400Mb (it's > ok), but > > >virtual > > > > So you are saying that there are times when phys-memory usage goes > > significantly > > above 1G memory. If that's the case then it defenitely is not an > issue > > with high mem. > > Yes, there are cases when phys-memory goes above 1G and even takes > all 2G. > There is no problem. > > > >memory is more than 2Gb. So system begin to swap, although real > memory > > >isn't overfilled. > > > > > > > What is getting swapped ? How did you find out that system is > getting > > swapped ? > > I think that it is getting swapped due to prense of kswapd in the > 'top' > of proccesses and increasing load on the file system (accordintly to > vmstat > output). In general system slows down, expecially it's notably on > java > applications perfomance. > > > I'm not an expert, but I've a feeling that you probably need to > play > > with some proc > > variables. System memory pages can get swapped out if the amount of > phys mem > > ory falls below some limit. BTW which 2.6 kernel are you using.. > > I think system 'see' that total virtual memory of applications is > bigger than it has physical memory, so it begin preliminarily > swapping > to avoid situation of lack of memory or something like this.. I'm not > expert too and this is just my guess. > > Can anybody tell me what man pages and /proc variables help me to > resolve this issue? Have you tried /proc/meminfo? If you have the kernel source tree in your system, you can get more info about /proc/meminfo in linux-2.6.x/Documentation/filesystems/proc.txt file. You should implement a script to collect some key values from /proc/meminfo in order to know when swap area is increasing and how the size of physical memory behaves along the time. BR, Mauricio Lin. ____________________________________________________ -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
