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Subject: hacking - aio_sendfile()
From: Adrian Chadd <adrian@freebsd.org>
To: freebsd-current <freebsd-current@freebsd.org>
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X-List-Received-Date: Wed, 10 Jul 2013 23:36:24 -0000

Hiya,

I've started writing an aio_sendfile() syscall.

http://people.freebsd.org/~adrian/ath/20130710-aio-sendfile-3.diff

Yes, the diff is against -HEAD and not stable/9.

It's totally horrible, hackish and likely bad. I've only done some
very, very basic testing to ensure it actually works; i haven't at all
stress tested it out yet. It's also very naive - I'm not at all doing
any checks to see whether I can short-cut to do the aio there and
then; I'm always queuing the sendfile() op through the worker threads.
That's likely stupid and inefficient in a lot of cases, but it at
least gets the syscall up and working.

I'd like some feedback and possibly some help in stress testing it to
make sure it's functioning well.

Thanks,


-adrian