VM Related question
I have noticed with my current kernel that after the system is idle for a while, say 10 hours or so, that everything seems to be swapped out to disk. So when I come in the next morning it starts swapping everything like crazy in from disk. Is this a known characteristic of the VM. I seem to remember this with all 2.4 kernels tried to date.
Whats the point of swapping out to disk in circumstances like this?
Currently I am using 2.4.18-rc2-ac2, with apps like mozilla, dozen xterms, xemacs, staroffice etc.
Cheers,
Tony.
Quoted 9 lines · Tony Clarke
I have noticed with my current kernel that after the system is idle for a while, say 10 hours or
so, that everything seems to be swapped out to disk. So when I come in the next morning
it starts swapping everything like crazy in from disk. Is this a known characteristic of the
VM. I seem to remember this with all 2.4 kernels tried to date.
Quoted 4 lines
Whats the point of swapping out to disk in circumstances like this?
Currently I am using 2.4.18-rc2-ac2, with apps like mozilla, dozen xterms, xemacs, staroffice etc.
The kernel makes no decision to swap just because you left the machine. But your distro probably runs "updatedb" at night. Updatedb reads all the directories in all your filesystems, so it tends to use a lot of cache. This activity pushes lots of other stuff into swap.
You may of course change your crontab to runn updatedb less often, or configure updatedb to skip directory trees where you expect little change. (/usr perhaps...)
Helge Hafting
Quoted 15 lines
Quoted 9 lines
I have noticed with my current kernel that after the system is idle for a while, say 10 hours or
so, that everything seems to be swapped out to disk. So when I come in the next morning
it starts swapping everything like crazy in from disk. Is this a known characteristic of the
VM. I seem to remember this with all 2.4 kernels tried to date.Quoted 5 lines
Whats the point of swapping out to disk in circumstances like this?
Currently I am using 2.4.18-rc2-ac2, with apps like mozilla, dozen xterms, xemacs, staroffice etc.
Quoted 6 lines
The kernel makes no decision to swap just because you left the machine. But your distro probably runs "updatedb" at night. Updatedb reads all the directories in all your filesystems, so it tends to use a lot of cache. This activity pushes lots of other stuff into swap.
Yep. That makes sense. /proc/slabinfo looks like
inode_cache 60311 60312 512 8616 8616 1 dentry_cache 60301 63930 128 2131 2131 1 buffer_head 35115 40620 128 1348 1354 1
this is on a 256mb machine.
Would I be right in saying that the only way that memory gets reclaimed , is by some process requesting memory or by some process waking up and having a load of page faults?
Cheers,
Tony.