From: Fredrik Tolf <fredrik@dolda2000.com>
To: Dave Chinner <david@fromorbit.com>
Cc: xfs@oss.sgi.com
Subject: Re: Extreme I/O latency
Date: Tue, 2 Oct 2012 16:31:48 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.02.1210021629090.3390@shack.dolda2000.com> (raw)
In-Reply-To: <20121002050806.GO23520@dastard>
On Tue, 2 Oct 2012, Dave Chinner wrote:
> On Tue, Oct 02, 2012 at 05:25:53AM +0200, Fredrik Tolf wrote:
>> On Tue, 2 Oct 2012, Dave Chinner wrote:
>>> On Tue, Oct 02, 2012 at 03:53:08AM +0200, Fredrik Tolf wrote:
>>> What is a "simple IO operation"?
>>
>> Sorry, what I meant by "simple" is mostly on the interface level.
>> Like, a single syscall (with far less than a page of data in the
>> case of read or write), or, in this case, reading a single mmap'ed
>> page.
>
> Which might be "simple" by themselves, but when an application is
> doing thousands of such operations a second, the result is far from
> simple....
Certainly; though I seem to be bad at communicating it, the point I was
trying to make is that it is, from the point of view of userspace,
individual calls that take extremely long, rather than total throughput
being poor. :)
--
Fredrik Tolf
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
prev parent reply other threads:[~2012-10-02 19:45 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-02 1:53 Extreme I/O latency Fredrik Tolf
2012-10-02 2:20 ` Dave Chinner
2012-10-02 3:25 ` Fredrik Tolf
2012-10-02 5:08 ` Dave Chinner
2012-10-02 14:31 ` Fredrik Tolf [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=alpine.DEB.2.02.1210021629090.3390@shack.dolda2000.com \
--to=fredrik@dolda2000.com \
--cc=david@fromorbit.com \
--cc=xfs@oss.sgi.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.