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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 ` 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
2012-09-30 12:16 Uwaysi Bin Kareem

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