Re: [Qemu-devel] [RFC PATCH 3/3] qemu-coroutine: use a ring per thread for the pool

[Paolo Bonzini <pbonzini@redhat.com>]

On 28/11/2014 13:49, Peter Lieven wrote:
>>> Idea:
>>> >>  If the release_pool is full why not put the coroutine in the thread alloc_pool instead of throwing it away? :-)
>> > Because you can only waste 64 coroutines per thread.  But numbers cannot

s/only//

>> > be sneezed at, so it's worth doing it as a separate patch.
> What do you mean by that? If I use dataplane I will fill the global pool and never use it okay, but
> then I use thread local storage only. So I get the same numbers as in my thread local storage only version.

Right.  I didn't want to waste the coroutines.  But it's not 64
coroutines per VCPU thread, it's just 64 coroutines for the global
iothread because all the dataplane threads are guaranteed to use
ioeventfd.  Let's do it. :)

Can I add your Signed-off-by to the patch?

Paolo

> Maybe it is an idea to tweak the POOL_BATCH_SIZE * 2 according to what is really attached. If we
> have only dataplane or ioeventfd it can be POOL_BATCH_SIZE * 0 and we even won't waste those
> coroutines oxidating in the global pool.