public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Brian Twichell <tbrian@us.ibm.com>
To: David Lang <david.lang@digitalinsight.com>
Cc: linux-kernel@vger.kernel.org, mbligh@mbligh.org,
	slpratt@us.ibm.com, anton@samba.org
Subject: Re: Database regression due to scheduler changes ?
Date: Mon, 07 Nov 2005 17:06:10 -0600	[thread overview]
Message-ID: <436FDDE2.4000708@us.ibm.com> (raw)
In-Reply-To: <Pine.LNX.4.62.0511071431030.9339@qynat.qvtvafvgr.pbz>

David Lang wrote:

>   If I am understanding the data you posted, it looks like you are 
> useing sched_yield extensivly in your database. 

Yes, I've seen problems in the past with workloads that use sched_yield 
heavily.

But bear in mind, the ~2700 sched_yields shown in the schedstats 
occurred over a 9 minute period. 
That means that sched_yield is being called at a rate of around 5 per 
second -- this is not a heavy user of sched_yield.

To put this into a broader perspective, this workload has around 270 
tasks, and the context switch rate is around
45,000 per second.




  reply	other threads:[~2005-11-07 23:06 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-11-07 22:17 Database regression due to scheduler changes ? Brian Twichell
2005-11-07 22:35 ` David Lang
2005-11-07 23:06   ` Brian Twichell [this message]
2005-11-08  0:51     ` Nick Piggin
2005-11-08  1:15       ` Anton Blanchard
2005-11-08  1:34         ` Martin J. Bligh
2005-11-08  1:46           ` Nick Piggin
2005-11-08  1:48             ` Nick Piggin
2005-11-08  1:58             ` Martin J. Bligh
2005-11-08  2:04             ` David Lang
2005-11-08  2:12               ` Martin J. Bligh
2005-11-08  2:15               ` Nick Piggin
2005-11-09  5:03       ` Brian Twichell
     [not found]         ` <43718DFE.3040600@yahoo.com.au>
2005-11-14 23:03           ` Brian Twichell
2005-11-08  2:31   ` Byron Stanoszek
2005-11-07 22:47 ` linux-os (Dick Johnson)
2005-11-08  3:54   ` Nick Piggin
     [not found] <43715361.3070802@us.ibm.com>
2005-11-09  2:14 ` Andrew Theurer

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=436FDDE2.4000708@us.ibm.com \
    --to=tbrian@us.ibm.com \
    --cc=anton@samba.org \
    --cc=david.lang@digitalinsight.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mbligh@mbligh.org \
    --cc=slpratt@us.ibm.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