lkml.org 
[lkml]   [2003]   [Feb]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
Subjectanticipatory scheduling questions
Hello, 

I have just installed 2.5.63-mm1 on my system and have been performing a very simple benchmarks. Here are
my first results when compared against a RedHat 2.4.20-2.54 kernel:

(All times expressed as total times)

1. time dd if=/dev/zero of=/tmp/p bs=1024k count=256
2.5.63-mm1 -> 0m12.737s
2.4.20-2.54 -> 0m17.704s

2. time cp /tmp/p /tmp/q
2.5.63-mm1 -> 0m41.108s
2.4.20-2.54 -> 0m51.939s

3. time cmp /tmp/p /tmp/q
2.5.63-mm1 -> 1m7.349s
2.4.20-2.54 -> 0m58.966s

4. time cmp /dev/zero /tmp/q
2.5.63-mm1 -> 0m17.965s
2.4.20-2.54 -> 0m14.038s

The question is, why, apparently, is anticipatory scheduling perfomring worse than 2.4.20? Indeed, this can be
tested interactively with an application like Evolution: I have configured Evolution to use 2 dictionaries (English
and Spanish) for spell checking in e-mail messages. When running 2.4.20, if I choose to reply to a large
message, it only takes a few seconds to read both dictionaries from disk and perform the spell checking.
However, on 2.5.63-mm1 the same process takes considerably longer. Any reason for this?

Thanks!

Best regards,

Felipe Alfaro Solana

--
______________________________________________
http://www.linuxmail.org/
Now with e-mail forwarding for only US$5.95/yr

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

\
 
 \ /
  Last update: 2005-03-22 13:33    [W:0.042 / U:0.828 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site