On Wed, Jul 15, 2020 at 10:33 AM Pavel Begunkov <asml.silence@xxxxxxxxx> wrote: > > On 14/07/2020 14:55, Miklos Szeredi wrote: > > On Tue, Jul 14, 2020 at 1:36 PM Pavel Begunkov <asml.silence@xxxxxxxxx> wrote: > >> > >> On 14/07/2020 11:07, Miklos Szeredi wrote: > >>> On Tue, Jul 14, 2020 at 8:51 AM Pavel Machek <pavel@xxxxxxx> wrote: > >>>> > >>>> Hi! > >>>> > >>>>>> At first, I thought that the proposed system call is capable of > >>>>>> reading *multiple* small files using a single system call - which > >>>>>> would help increase HDD/SSD queue utilization and increase IOPS (I/O > >>>>>> operations per second) - but that isn't the case and the proposed > >>>>>> system call can read just a single file. > >>>>> > >>>>> If you want to do this for multple files, use io_ring, that's what it > >>>>> was designed for. I think Jens was going to be adding support for the > >>>>> open/read/close pattern to it as well, after some other more pressing > >>>>> features/fixes were finished. > >>>> > >>>> What about... just using io_uring for single file, too? I'm pretty > >>>> sure it can be wrapped in a library that is simple to use, avoiding > >>>> need for new syscall. > >>> > >>> Just wondering: is there a plan to add strace support to io_uring? > >>> And I don't just mean the syscalls associated with io_uring, but > >>> tracing the ring itself. > >> > >> What kind of support do you mean? io_uring is asynchronous in nature > >> with all intrinsic tracing/debugging/etc. problems of such APIs. > >> And there are a lot of handy trace points, are those not enough? > >> > >> Though, this can be an interesting project to rethink how async > >> APIs are worked with. > > > > Yeah, it's an interesting problem. The uring has the same events, as > > far as I understand, that are recorded in a multithreaded strace > > output (syscall entry, syscall exit); nothing more is needed> > > I do think this needs to be integrated into strace(1), otherwise the > > usefulness of that tool (which I think is *very* high) would go down > > drastically as io_uring usage goes up. > > Not touching the topic of usefulness of strace + io_uring, but I'd rather > have a tool that solves a problem, than a problem that created and honed > for a tool. Sorry, I'm not getting the metaphor. Can you please elaborate? Thanks, Miklos
