public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jens Axboe <jaxboe@fusionio.com>
To: Shaohua Li <shaohua.li@intel.com>
Cc: lkml <linux-kernel@vger.kernel.org>, Vivek Goyal <vgoyal@redhat.com>
Subject: Re: [PATCH 0/3]CFQ: add think time check for service tree and group
Date: Mon, 11 Jul 2011 13:27:53 +0200	[thread overview]
Message-ID: <4E1ADE39.6090609@fusionio.com> (raw)
In-Reply-To: <CANejiEXryM=hawNjQZPYEM2L97+gUYqHQ_YQJ5p5gLTvBkC25Q@mail.gmail.com>

On 2011-07-11 07:44, Shaohua Li wrote:
> 2011/7/4 Shaohua Li <shaohua.li@intel.com>:
>> Hi,
>>  Currently when the last queue of a service tree/group is empty, CFQ
>> doesn't expire the queue. This is to allow requests from the tree/group
>> come soon, so tree/group doesn't miss its share. But if the think time
>> is big, the assumption isn't correct. idling the queue is just wasting
>> bandwidth.
>>
>> Originally I was hoping this can resolve Vivek's fsync issue, but it
>> doesn't. The fsync issue is caused by queue idling. But since think time
>> check only helps for think time above default queue idle time (8ms),
>> think time check doesn't help.
>>
>> On the other hand, think time check is still helpful for queues with
>> think time. I had test case in follow patches show throughput
>> improvement without sacrifice tree/group shares.
>>
> Jens,
> can you look at the patches? I refreshed some patches in replying
> Vivek, I can resend if required.

Please resend the series after a refresh like that, otherwise I tend to
lose track of the various things flying around.

-- 
Jens Axboe


  reply	other threads:[~2011-07-11 11:27 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-04  5:36 [PATCH 0/3]CFQ: add think time check for service tree and group Shaohua Li
2011-07-11  5:44 ` Shaohua Li
2011-07-11 11:27   ` Jens Axboe [this message]
2011-07-11 13:05   ` Vivek Goyal

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=4E1ADE39.6090609@fusionio.com \
    --to=jaxboe@fusionio.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=shaohua.li@intel.com \
    --cc=vgoyal@redhat.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