lkml.org 
[lkml]   [1998]   [Sep]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] scheduler patch, faster still

On Mon, 28 Sep 1998 yodaiken@chelm.cs.nmt.edu wrote:

> Is it? And, isn't Richard arguing that his change makes sense only for
> long queues?

aggreed. 'long runqueues' are definitely a red herring. Very big (Linux)
servers and even artificial 'exploit' programs could not show any RL case
where there are long runqueues. Eg. someone at Kiva (now they are
Netscape) has asked the same questions and has run statistics on a very
big webserver and the average runqueue length was around 3, maxing out at
15. (the article showing exact numbers can be found via DejaNews) Other
reports show similar results. (i too tried to trigger very long runqueues
for server type load, but failed). [the reason i tried to do some
statistics was that i have a solution for the 'wake one' and 'thundering
herd' theoretical problem, but under Linux it's a definit non-problem. I
have tested an Apache test-setup which served some 1200 small static pages
per second]

Long runqueues might be a problem on other OSs, but not on Linux. (or if
yes, please show me the case)

(barring one case, when there are alot of CPU-bound processes around, in
which case those processes waste so much cache resources anyway)

-- mingo


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:44    [W:0.109 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site