Re: Abysmal interactive performance on 2.4.linus

Frank de Lange (lkml-frank@unternet.org)
Mon, 12 Nov 2001 23:56:42 +0100


On Mon, Nov 12, 2001 at 03:05:56PM -0500, Jeff Garzik wrote:
> Can you try 2.4.13ac6 (not 7/8), and 2.2.20, and post a comparison?

Here's the results from some tests I did:

2.2.20
======
without filesystem activity
no slowdowns observed
time ls -al /usr/|sort -k 5 -n
real 0m0.121s
user 0m0.000s
sys 0m0.090s

with filesystem activity on ext2
no slowdowns observed
time ls -al /opt/|sort -k 5 -n
real 0m0.079s
user 0m0.010s
sys 0m0.100s

2.4.13-ac5
==========
no slowdowns observed
without filesystem activity
time ls -al /usr/|sort -k 5 -n
real 0m0.142s
user 0m0.000s
sys 0m0.000s

with filesystem activity on ext2
no slowdowns observed
time ls -al /opt/|sort -k 5 -n
real 0m0.022s
user 0m0.020s
sys 0m0.010s

with filesystem activity on reiserfs
- it took 31 seconds to just open this small ( < 1 kb) text file (which
resides in my home directory, on an ext2 filesystem) in vi...
time ls -al /usr/|sort -k 5 -n
real 0m6.136s
user 0m0.020s
sys 0m0.020s

2.4.15-pre4
===========
without filesystem activity
no slowdowns observed
time ls -al /usr/|sort -k 5 -n
real 0m0.081s
user 0m0.010s
sys 0m0.010s

with filesystem activity on ext2
no slowdowns observed
time ls -al /usr/|sort -k 5 -n
real 0m0.146s
user 0m0.000s
sys 0m0.020s

with filesystem activity on reiserfs
system behaviour erratic, some slowdowns
time ls -al /opt|sort -k5 -n
real 0m13.232s
user 0m0.020s
sys 0m0.010s

Seems that reiserfs is the common factor here, at least on my box. This is a 35
GB reiserfs filesystem, app 80% used, both large and small files.

As said in my previous message, the numbers themselves don't mean squat. It is
the large delays (the fact that user+sys <<< real) which are the problem here.

Any other magic anyone wants me to perform? Hans, you reading this?

Cheers//Frank

-- 
  WWWWW      _______________________
 ## o o\    /     Frank de Lange     \
 }#   \|   /                          \
  ##---# _/     <Hacker for Hire>      \
   ####   \      +31-320-252965        /
           \ lkml-frank@unternet.org  /
            -------------------------
 [ "Omnis enim res, quae dando non deficit, dum habetur
    et non datur, nondum habetur, quomodo habenda est."  ]
-
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/