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Re: [Qemu-devel] Re: [PATCH] QEMUFileBuffered: indicate that we're ready
Re: [Qemu-devel] Re: [PATCH] QEMUFileBuffered: indicate that we're ready when the underlying file is ready
Thu, 19 Aug 2010 16:12:01 +0300
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On 08/03/2010 04:00 PM, Luiz Capitulino wrote:
On Tue, 03 Aug 2010 09:12:52 +0300
Avi Kivity<address@hidden> wrote:
On 07/07/2010 07:44 PM, Avi Kivity wrote:
QEMUFileBuffered stops writing when the underlying QEMUFile is not ready,
and tells its producer so. However, when the underlying QEMUFile becomes
ready, it neglects to pass that information along, resulting in stoppage
of all data until the next tick (a tenths of a second).
Usually this doesn't matter, because most QEMUFiles used with QEMUFileBuffered
are almost always ready, but in the case of exec: migration this is not true,
due to the small pipe buffers used to connect to the target process. The
result is very slow migration.
Fix by detecting the readiness notification and propagating it. The detection
is a little ugly since QEMUFile overloads put_buffer() to send it, but that's
the suject for a different patch.
I've queued this fix and another one in a 'for-0.13' branch and was planning
to send a pull request as soon as Anthony called for 0.13 fixes, however
this didn't happen yet and I forgot.
I don't want to take over Cam's longest-time-to-apply record, so someone
apply this please. 0.13 and mainline.
error compiling committee.c: too many arguments to function