Am 21.06.2016 um 15:18 schrieb Dr. David Alan Gilbert:
* Peter Lieven (p...@kamp.de) wrote:
Hi,
while upgrading from Qemu 2.2.0 to Qemu 2.5.1.1 I noticed that the RSS memory
usage has heavily increased.
We use hugepages so the RSS memory does not include VM memory. In Qemu 2.2.0 it
used to be ~30MB per vServer
and increased to up to 300 - 400MB for Qemu 2.5.1.1 (same with master). The
memory increases over time, but seems
not to grow indefinetly. I tried to bisect, but had no result so far that made
sense. I also tried valgrind / massif, but
valgrind does not see the allocation (at least at exit) and massif fails to
rund due to - so it pretends - heap corruption.
Any help or ideas how to debug further would be appreciated.
I think I'd try stripping devices off; can you get a similar difference
to happen with a guest with no USB, no hugepages, no VGA and a simple
locally stored IDE disk?
If you're having trouble bisecting is it possible it's a change
in one of the libraries it's linked against?
There was someone asking the other day on #qemu who had a setup that
was apparently using much more RAM than expected and we didn't
manage to track it down but I can't remember the version being used.
I currently trying to track the increased usage from release to release. The
first increase of RSS usage from ~25MB to ~35MB directly
after machine setup is introduced by this patch:
commit ba3f4f64b0e941b9e03568b826746941bef071f9
Author: Paolo Bonzini <pbonz...@redhat.com>
Date: Wed Jan 21 12:09:14 2015 +0100
exec: RCUify AddressSpaceDispatch
Note that even after this patch, most callers of address_space_*
functions must still be under the big QEMU lock, otherwise the memory
region returned by address_space_translate can disappear as soon as
address_space_translate returns. This will be fixed in the next part
of this series.
Reviewed-by: Fam Zheng <f...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
@Paolo, @Fam, any idea?
Thanks,
Peter
