All of lore.kernel.org
 help / color / mirror / Atom feed
From: Uwaysi Bin Kareem <uwaysi.bin.kareem@paradoxuncreated.com>
To: linux-kernel@vger.kernel.org
Subject: The 10ms averager in fair.c
Date: Sun, 30 Sep 2012 13:44:14 +0200	[thread overview]
Message-ID: <op.wlf5j0i76426ze@localhost.localdomain> (raw)

Hiya. I just had an initial look at fair.c

There seems to be a 10ms averager in there?

You are aware that that means you work on delayed values?

Isn`t that counterintuitive to the principle of sharing?

That means short bursts of cpu-use will be filtered out, and given less  
cpu time.
Starting applications won`t have their cpu-usage before 5ms, which is  
quite a bit on modern machines. Well if you use a linearphase filter, I  
don`t know what kind of averager you use. The best would ofcourse be to  
use a minimalphase gaussian averager. Which might be overkill. Atleast a  
one-pole iir, buf = buf + (-buf + in) * cut)); One pole IIRs also have a  
better frequency response.

When you are working with low-latencies, wouldn`t it be better if such  
things are tuned for target latency. I think few care about latency after  
0.2ms. So say the filter should be set to 0.4ms max.

Why would you want to filter cpu-usage also really?

Peace Be With You.

(please CC me.)

             reply	other threads:[~2012-09-30 11:44 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-30 11:44 Uwaysi Bin Kareem [this message]
2012-09-30 19:18 ` The 10ms averager in fair.c Uwaysi Bin Kareem
     [not found] ` <1349064397.6957.26.camel@marge.simpson.net>
2012-10-01 13:24   ` Uwaysi Bin Kareem
     [not found]     ` <1349146202.7086.23.camel@marge.simpson.net>
2012-10-02  7:04       ` Uwaysi Bin Kareem
2012-10-02 17:25       ` The 10ms averager in fair.c + granularity Uwaysi Bin Kareem
2012-10-03 15:14       ` Uwaysi Bin Kareem
2012-10-04 12:20         ` el es
2012-10-03 20:26       ` Doom 3 perfect on linux Uwaysi Bin Kareem
2012-10-04 10:23       ` RME Fireface UCX in Classcompliant USB-mode, is not working? Uwaysi Bin Kareem
2012-10-05 19:54       ` The 10ms averager in fair.c Uwaysi Bin Kareem
2012-10-02  6:56   ` Uwaysi Bin Kareem
     [not found]     ` <1349169555.7086.48.camel@marge.simpson.net>
2012-10-02  8:07       ` Uwaysi Bin Kareem
     [not found]         ` <1349176973.7086.96.camel@marge.simpson.net>
2012-10-02  9:28           ` Uwaysi Bin Kareem
  -- strict thread matches above, loose matches on Subject: below --
2012-09-30 12:16 Uwaysi Bin Kareem

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=op.wlf5j0i76426ze@localhost.localdomain \
    --to=uwaysi.bin.kareem@paradoxuncreated.com \
    --cc=linux-kernel@vger.kernel.org \
    /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.