Re: [patch 2/2] QEMU: decrease console "refresh rate" with -nographic

Marcelo Tosatti
2008-04-15T15:04:23Z

On Tue, Apr 15, 2008 at 05:45:28PM +0300, Avi Kivity wrote:
> Anthony Liguori wrote:
> >
> >Why did we ever need sigtimedwait() anyway? Even if we were
> >select()ing within the VCPU context, we should break out of the
> >select() on signal delivery.
> >
>
> select() is no good since if the signal is delivered after the select(),
> but before entry into guest mode, it is lost. pselect() might work, but
> its is not supported on all hosts, and it (AFAICT) delivers the signals
> by calling their handlers, which is slow and unnecessary.

Anthony tested a patch using signalfd:

http://people.redhat.com/~mtosatti/io-thread-select-timeout

Which is only available on newer hosts. I guess the signals will have to
stay for older hosts.