[opensuse-amd64] /proc/kcore
Hello, recently I got a second AMD Opteron Dual Core and new RAM for my computer. It seems that everything (SLES10) works fine but as I checked the available disk space I saw that the root partition is complete. The reason for this is the file /proc/kcore. Can someone tell me why /proc/kcore can have a size of 5 GB when the RAM has only a size of 4GB? I thought /proc/kcore is a sort of image of the kernel and has the same size as RAM + some kB. Could someone help me please. Best regards, Christine -- Universität des Saarlandes AG Prof. Dr. Christoph Becher Fachrichtung 7.3 (Technische Physik) Geb. E2.6, Zimmer 2.04 D-66123 Saarbrücken Phone:+49(0)681 302 3418 Fax: +49(0)681 302 4676 E-mail: c.kreuzer@mx.uni-saarland.de --------------------------------------------------------------------- To unsubscribe, e-mail: opensuse-amd64+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-amd64+help@opensuse.org
It seems that everything (SLES10) works fine but as I checked the available disk space I saw that the root partition is complete. The reason for this is the file /proc/kcore. Can someone tell me why /proc/kcore can have a size of 5 GB when the RAM has only a size of 4GB?
The /proc directory is a filesystem on its own and does not take up any diskspace. When you unmount /proc, the directory /proc is empty. The file /proc/kcore represents your physical memory (minus a few kilobytes by the looks of it), is part of the proc filesystem and does not take up disk space. You can get a list of current mounts with the mount command (no options). Perhaps /proc wasn't mounted at some stage, and some process wrote into /proc and onto the disk? Check /proc is mounted now. Temporarily unount /proc and check that the directory is empty; if not, delete everything in it and mount /proc again. Check there is an entry for /proc in /etc/fstab, and that it gets mounted at boot. Check the size of your root filesystem with du -x / Be careful to always use -x here, and make sure you don't accidentally include other filesystems in the listing. For example du -x /* will give you the size of /proc as well as others, but you never want to know the size of filesystems like /proc (or sys, devfs) as they're all fakes without disk space. Keep hunting for your disk use, and use df and mount to see where filesystems start. Btw this list is specific for 64 bit issues, which yours is not and your question would be better asked on one of the general lists (there is a very good German one too). HTH, Volker -- Volker Kuhlmann is list0570 with the domain in header http://volker.dnsalias.net/ Please do not CC list postings to me. --------------------------------------------------------------------- To unsubscribe, e-mail: opensuse-amd64+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-amd64+help@opensuse.org
On Monday 05 February 2007 22:04, Christine Kreuzer wrote:
Hello,
recently I got a second AMD Opteron Dual Core and new RAM for my computer. It seems that everything (SLES10) works fine but as I checked the available disk space I saw that the root partition is complete. The reason for this is the file /proc/kcore.
/proc is outside the root partition, it doesn't exist on disk.
Can someone tell me why /proc/kcore can have a size of 5 GB when the RAM has only a size of 4GB?
There are holes in the memory map, used for memory mapped IO and some other things. These holes can be quite large in some cases and 1-2GB is not uncommon. The memory hole are usually below 4GB because many devices cannot address more than 4GB; the RAM continues beyond that. You can see the memory map as reported by the BIOS with head -30 /var/log/boot.msg. Only "usable" is real memory.
I thought /proc/kcore is a sort of image of the kernel and has the same size as RAM + some kB.
Yes, just some can be pretty large. -Andi --------------------------------------------------------------------- To unsubscribe, e-mail: opensuse-amd64+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-amd64+help@opensuse.org
participants (3)
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Andi Kleen
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Christine Kreuzer
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Volker Kuhlmann