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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Tue, 14 Jul 2020 10:07:02 +0200
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Subject: Re: [PATCH 0/3] readfile(2): a new syscall to make open/read/close faster
To:     Pavel Machek <pavel@denx.de>
Cc:     Greg KH <gregkh@linuxfoundation.org>,
        Jan Ziak <0xe2.0x9a.0x9b@gmail.com>,
        Linux API <linux-api@vger.kernel.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org,
        linux-man <linux-man@vger.kernel.org>,
        Michael Kerrisk <mtk.manpages@gmail.com>, shuah@kernel.org,
        Al Viro <viro@zeniv.linux.org.uk>, io-uring@vger.kernel.org
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On Tue, Jul 14, 2020 at 8:51 AM Pavel Machek <pavel@denx.de> 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.

I think that's quite important as io_uring becomes mainstream.

Thanks,
Miklos