Messages in this thread | | | Date | Wed, 21 May 2008 01:04:32 +0200 (CEST) | From | Christian Kujau <> | Subject | kswapd busy but not swapping |
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Hi,
I noticed that the [kswapd0] thread was eating 3-7% cpu time but no swapspace has been used yet. This is with a just booted 2.6.25.4 system, currently with some disk i/o going on.
So I figured that kswapd might not be responsible for "swapping" after all, although the name suggests it. Grep'ing Documentation/ for kswapd did not reveal much. Is the paper from Kanoj[0] still valid for 2.6 kernels? The SGI page referenced in Documentation/kernel-docs.txt is down, but there's a .txt version on [1] which tells me:
"When memory runs low, and a process can not find a free page, it wakes up kswapd, the memory stealer"
So, if I'd run low on memory, kswapd would be active. But I don't see that in free(1):
# free -m total used free shared buffers cached Mem: 2023 1662 360 0 820 315 -/+ buffers/cache: 526 1496 Swap: 1505 0 1505
If you're interested, there are more details at http://nerdbynature.de/bits/2.6.25.4/kswapd
Thanks, Christian.
[0] http://reality.sgi.com/kanoj_engr/vm229.html [1] http://www.cse.unsw.edu.au/~neilb/oss/linux-commentary/ -- BOFH excuse #197:
I'm sorry a pentium won't do, you need an SGI to connect with us.
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