Am 25.06.2011 um 10:38 schrieb Jan Kiszka:
On 2011-04-13 22:16, Aurelien Jarno wrote:
On Mon, Apr 11, 2011 at 10:27:41PM +0200, Jan Kiszka wrote:
These patches were posted before. They bring down the overhead of
the
io-thread mode for TCG here, specifically when emulating SMP.
The major change in this version, besides rebasing, is the
exclusion of
KVM from the main loop polling optimization.
Jan Kiszka (3):
Do not drop global mutex for polled main loop runs
Poll main loop after I/O events were received
Do not kick vcpus in TCG mode
cpus.c | 2 +-
sysemu.h | 2 +-
vl.c | 22 ++++++++++++++++------
3 files changed, 18 insertions(+), 8 deletions(-)
Thanks for working on improving the io-thread with TCG. Your patches
make sense, but they don't seems to fix the slowdown observed when
enabling the io-thread. Well maybe they were not supposed to. This is
for example the results of netperf between guest and host using
virtio:
no io-thread 122 MB/s
io-thread 97 MB/s
io-thread + patches 98 MB/s
Given that everyone seems to agree that these patches are a step into
the right direction (for the current TCG locking architecture at
least),
can we please finally apply them? They do have positive impact in some
use cases. If rebasing is required (I don't think so), just let me
know.
BTW, did you make any progress with tracing the remaining issues?
I've tested these together with Paolo's fixes, but it still hangs on
Darwin. Doesn't appear to make it worse though.
Andreas
