Re: [Qemu-devel] [PATCH 1/2] win32: do not set CPU affinity

[Roy Tam]

2013/2/21 Roy Tam <address@hidden>:
> 2013/2/21 Paolo Bonzini <address@hidden>:
>> Il 21/02/2013 01:35, Roy Tam ha scritto:
>>>> > QEMU system emulation has been thread-safe for a long time, and
>>>> > setting the CPU affinity is hurting performance badly.  Remove
>>>> > the bogus code.
>>>> >
>>>> > Jacob Kroon reports that the time to boot his VxWorks image goes from
>>>> > "3 minutes passed and I still haven't made it that far" to ~140s.
>>>> >
>>> Yes it does work better for fdostest.img, but when I tried to boot
>>> ttylinux-i686-14.0.iso, qemu freezes after showing "loading vmlinuz
>>> ..."
>>>
>>
>> Did it work without the patch?
>
> Yes, at least linux kernel starts but stalls when hitting IO-APIC
> thingy, with noapic boot switch it stalls after detecting ttyS0
>
> With patch, QEMU is unresponsive when loading vmlinuz (not even
> showing "Decompressing Linux" message)

Clarify that it boots fine sometimes, but when QEMU freezes, there is
a thread busy-waiting(seems so):
http://i.imgur.com/LUJjd8r.png

>
>>
>> Paolo