Re: swapping when there's a free memory

From: Pavel Machek
Date: Sun Apr 25 2010 - 03:14:39 EST


Hi!

> I captured this output of vmstat. The machine was freeing cache and
> swapping out pages even when there was a plenty of free memory.
>
> The machine is sparc64 with 1GB RAM with 2.6.34-rc4. This abnormal
> swapping happened during running spadfsck --- a fsck program for a custom
> filesystem that caches most reads in its internal cache --- so it reads
> buffers and allocates memory at the same time.
>
> Note that sparc64 doesn't have any low/high memory zones, so it couldn't
> be explained by filling one zone and needing to allocate pages in it.

Fragmented memory + high-order allocation?

> This abnormal behavior doesn't happen everytime, it happend about twice
> for many spadfsck attempts.

...yep, that would be random.
Pavel


--
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