Il 24/07/2013 03:28, liu ping fan ha scritto: > On Tue, Jul 23, 2013 at 6:30 PM, Paolo Bonzini <pbonz...@redhat.com> wrote: >> > Il 23/07/2013 04:53, liu ping fan ha scritto: >>> >> The scenior I can figure out is if adopting timeout of poll, then when >>> >> changing the deadline, we need to invoke poll, and set the new >>> >> timeout, right? >> > >> > Yes, you need to call aio_notify so that poll is reinvoked. >> > > I try to list the difference between alarm_timer and timeout of poll. > It includes thread-affinity, resolution and easy-use. > > Most of all, thread-affinity > The main issue with alarm timer is the affinity of timer_t with > threads. For linux, SIGEV_THREAD_ID has been supported for a very long > time and we already associate the signal with the specified thread. So > the only issue is left for other unix, we can emulate the affinity by > using SIGEV_THREAD and repost the event to the specified thread. > As to timeout of poll, it has the affinity of threads. > > Resolution: > alarm_timer provides higher resolution, but do we care about it?
With ppoll, is this true or just hearsay? (Without ppoll, indeed setitimer has 1 us resolution while poll has 1 ms; too bad that select has other problems, because select has also 1 us resolution). Paolo > easy-use: > The reset of the deadline as mentioned. > > Finally, I admit timeout of poll will save large chunk of platform-related > code.
