Subject: Re: 2.6 vs 2.4, ssh terminal slowdown
From: Lee Revell <rlrevell@joe-job.com>
To: Con Kolivas <kernel@kolivas.org>
Cc: gcoady@gmail.com, linux-kernel@vger.kernel.org
In-Reply-To: <200602081400.59931.kernel@kolivas.org>
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Date: Wed, 08 Feb 2006 02:43:58 -0500
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On Wed, 2006-02-08 at 14:00 +1100, Con Kolivas wrote:
> This is the terminal's fault. xterm et al use an algorithm to
> determine how fast your machine is and decide whether to jump scroll
> or smooth scroll. This algorithm is basically broken with the 2.6
> scheduler and it decides to mostly smooth scroll.
> 

Hmm, I've been having a similar problem for ages.  If I just do "ls" in
my home directory 10 or 20 times, approximately 20% of the time it's
"fast":

real    0m0.177s
user    0m0.028s
sys     0m0.027s

And the rest of the times it's "slow":

real    0m1.240s
user    0m0.036s
sys     0m0.040s

I rarely get anything in between - it's either ~1.2s or ~0.2s.

"time ls | cat" is always fast - 0.18 - 0.35s.

real    0m0.188s
user    0m0.014s
sys     0m0.018s

It has been this way as long as I can remember and it never made
sense...

Lee

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