Flexible I/O Tester development
 help / color / mirror / Atom feed
From: Jens Axboe <jaxboe@fusionio.com>
To: Steven Lang <tirea@google.com>
Cc: "fio@vger.kernel.org" <fio@vger.kernel.org>
Subject: Re: A commented out optimization...
Date: Thu, 2 Feb 2012 20:16:11 +0100	[thread overview]
Message-ID: <4F2AE0FB.3020201@fusionio.com> (raw)
In-Reply-To: <CAAUT-yO3JUwe_61XiKrxhQ2cD4NJOg+4k7ttxj_1D+wXY9P=gQ@mail.gmail.com>

On 2012-02-02 20:13, Steven Lang wrote:
> The only thing I can think is maybe there was some sort of other issue
> where perhaps a DMA IO was happening before the memory write,
> unrelated to any of the code there, but the write barrier just
> happened to fix it.  But even that seems like it would be a bit of a
> stretch to imagine it actually being a problem.

I was thinking that could've been the issue as well, but in that case it
would be a kernel (or driver) bug in that it didn't flush.

-- 
Jens Axboe


      reply	other threads:[~2012-02-02 19:16 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-01  1:40 A commented out optimization Steven Lang
2012-02-01  8:22 ` Jens Axboe
2012-02-01 21:46   ` Steven Lang
2012-02-02  8:03     ` Jens Axboe
2012-02-02 19:13       ` Steven Lang
2012-02-02 19:16         ` Jens Axboe [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4F2AE0FB.3020201@fusionio.com \
    --to=jaxboe@fusionio.com \
    --cc=fio@vger.kernel.org \
    --cc=tirea@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox