Date: Wed, 30 May 2007 09:55:11 -0700
From: Zach Brown <zach.brown@oracle.com>
To: Jens Axboe <jens.axboe@oracle.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Arjan van de Ven <arjan@infradead.org>, Andrew Morton <akpm@zip.com.au>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Ulrich Drepper <drepper@redhat.com>,
       Evgeniy Polyakov <johnpol@2ka.mipt.ru>,
       "David S. Miller" <davem@davemloft.net>,
       Suparna Bhattacharya <suparna@in.ibm.com>,
       Davide Libenzi <davidel@xmailserver.org>,
       Thomas Gleixner <tglx@linutronix.de>
Subject: Re: Syslets, Threadlets, generic AIO support, v6
Message-ID: <20070530165511.GB5488@mami.zabbo.net>
References: <20070529212718.GH7875@mami.zabbo.net> <20070530074031.GV15559@kernel.dk>
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> Yeah, it'll confuse CFQ a lot actually. The threads either need to share
> an io context (clean approach, however will introduce locking for things
> that were previously lockless), or CFQ needs to get better support for
> cooperating processes.

Do let me know if I can be of any help in this.

> For the fio testing, we can make some improvements there. Right now you
> don't get any concurrency of the io requests if you set eg iodepth=32,
> as the 32 requests will be submitted as a linked chain of atoms. For io
> saturation, that's not really what you want.

Just to be clear: I'm currently focusing on supporting sys_io_*() so I'm
using fio's libaio engine.  I'm not testing the syslet syscall interface
yet.

- z
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