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Date: Fri, 27 Jul 2007 12:55:08 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: QEMU Automated Testing (was [Qemu-devel] qemu Makefile.target
	vl.h hw/acpi.c hw/adlib.c ...)
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To: qemu-devel@nongnu.org
Cc: n schembr <nschembr@yahoo.com>

Paul Brook wrote:
>>> As Qemu cannot use multicore CPUs (partially due to missing thread
>>> safety), yet, you won't benefit from this unless you want to run
>>> multiple instances of Qemu in parallel.
>>>       
>> how close is thread safey?
>>     
>
> In a useful form: a fair way off.
>
> It's relatively simple to hack something together than runs. Making it work 
> correctly and go fast is much harder though. My current prototype (running on 
> 2 cores) runs about a quarter the speed of normal qemu, and dies shortly 
> after booting because the guest atomic synchronisation primitives don't work 
> right.
>   

This later problem seems like the hardest to solve to me.  Did you have 
any ideas here that don't involve hand coding the translation for atomic 
instructions?

Regards,

Anthony Liguori

> Either way, for a tinderbox or automated testing yo *do* have lots of 
> different tests you can run in parallel, so it doesn't matter that each qemu 
> instance only uses one core. We're only talking about small SMP here - maybe 
> 16 cores, but not thousands.
>
> Paul
>
>
>
>