From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [patch 2/2] QEMU: decrease console "refresh rate"
	with -nographic
Date: Tue, 15 Apr 2008 12:04:23 -0300
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Cc: kvm-devel@lists.sourceforge.net
To: Avi Kivity <avi@qumranet.com>
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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.


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