Re: [Qemu-devel] [PATCH 0/7] coroutine: optimizations

[Ming Lei]

On Fri, Nov 28, 2014 at 10:12 PM, Paolo Bonzini <address@hidden> wrote:
> As discussed in the other thread, this brings speedups from
> dropping the coroutine mutex (which serializes multiple iothreads,
> too) and using ELF thread-local storage.
>
> The speedup in perf/cost is about 30% (190->145).  Windows port tested
> with tests/test-coroutine.exe under Wine.

The data is very nice, and in my laptop, 'perf cost' can be decreased
from 244ns to 174ns.

BTW, the cost by using coroutine to run function isn't only from these
helpers(*_yield, *_enter, *_create, and perf-cost just measures
this part of cost), but also some implicit/invisible part. I have some
test cases which can show the problem. If someone is interested,
I can post them in list.


Thanks,
Ming Lei