Re: [Qemu-devel] [PATCH v2 0/3] Make thread pool implementation modular

[Paolo Bonzini]

Il 11/11/2013 18:59, Alex Bligh ha scritto:
> > Why is it necessary to push this task down into the host?  I don't
> > understand the advantage of this approach except that maybe it works
> > around certain misconfigurations, I/O scheduler quirks, or plain old
> > bugs - all of which should be investigated and fixed at the source
> > instead of adding another layer of code to mask them.
> 
> I can see an argument why a guest with two very differently
> performing disks attached might be best served by two worker
> threads, particularly if one such thread was in part CPU bound
> (inventing this use case is left as an exercise for the reader).

In most cases you want to use aio=native anyway, and then the QEMU
thread pool is entirely bypassed.

Paolo