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

Avi Kivity
2008-04-15T13:47:22Z

Anthony Liguori wrote:
> Avi Kivity wrote:
>> Anthony Liguori wrote:
>>>
>>> BTW, when we set O_ASYNC on the tap fd, we're eliminating
>>> O_NONBLOCK. This means that we have to poll loop select() when
>>> readv()'ing packets instead of just reading until hitting AGAIN.
>>> This means at least an extra syscall per packet.
>>
>> I didn't know that O_ASYNC and O_NONBLOCK were mutually exclusive.
>> Can you point me at the relevant documentation?
>
> I don't know that they are, but we're doing an:
>
> fcntl(fd, F_SETFL, O_ASYNC);
>
> F_SETFL is not additive so the previous O_NONBLOCK gets dropped.
>

Ah, I thought it's something fundamental I'm missing. The above is just
a bug.

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error compiling committee.c: too many arguments to function