swap or memory leak on recent master?

YONETANI Tomokazu y0n3t4n1 at gmail.com
Tue Jul 19 22:49:18 PDT 2011

On Tue, Jul 12, 2011 at 08:35:04PM -0700, Matthew Dillon wrote:
>     Well, the kernel memory allocator itself doesn't use swap, so it is
>     more likely a runaway user program (?) and not the kernel.  If tmpfs
>     is being used it could be something filling up the tmpfs mount, including
>     possibly a process with a descriptor open on an unlinked file.  That's
>     all I can think of.

I don't think this was the case, because I could go to single user mode
without a problem, and I could umount /tmp.

>     Under normal operation idle processes will eventually wind up getting
>     paged out since there is no sense tying up ram to hold them.  e.g.
>     things like getty and such, but these normally do not amount to very
>     much use.

This is rather subjective, but on a `good' kernel, the swap usage in
top's output stays something like this (it has 4Gbytes of physical memory)
  Swap: 8192M Total, 32M Used, 8192M Free
where as on a `bad' kernel,
  Swap: 8192M Total, 514M Used, 7678M Free, 6% Inuse

This looks odd to me, as I've never needed this much swap space even
when I was using 6 jails for pbulk.  I'm not using jails now.

The last known `good' kernel was built from source as of 1e7aaef,
but bisecting cannot be automatic because the later kernels are
a bit unstable (e.g., sometimes a process locks in objde1 or objde2
and pbulk stalls waiting for it).

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