Re: [PATCH] reiserfs speedup for 2.4.9+

[jogi@planetzork.ping.de]

On Sat, Sep 22, 2001 at 05:39:37PM -0400, Chris Mason wrote:
> 
> Hello everyone,

Hello Chris,

> Beau pointed me towards a performance bug in reiserfs, where reiserfs_write_super would be called excessively.  
> 
> Turns out that 2.4.9 included some new super handling code that 
> interacted poorly with how reiserfs uses kupdated calls to 
> write_super to trigger writebacks of metadata.
> 
> This is most obvious with benchmarks like bonnie++, where 
> 2.4.9 and 2.4.10 reiserfs do very poorly.
> 
> This patch makes things much better in my tests, I'd appreciate 
> a few more testers.  The only risk is reiserfs using slightly 
> more memory, but only if I've screwed something up.

Just to share my two cents. First I have to tell that the skipping
of alsaplayer playing .wav files I experienced during kernel compiles
or other activities is almost completly gone. Furthermore I did some
performance testing of kernel compiles (actions that are done:
untar kernel, patch kernel, make -j50 bzImage modules, 5 times in a
row). These are the results of plain 2.4.10-pre14aa1:

Elapsed (wall clock) time (h:mm:ss or m:ss): 6:25.90
Elapsed (wall clock) time (h:mm:ss or m:ss): 6:15.43
Elapsed (wall clock) time (h:mm:ss or m:ss): 6:01.95
Elapsed (wall clock) time (h:mm:ss or m:ss): 6:12.56
Elapsed (wall clock) time (h:mm:ss or m:ss): 6:35.61

And here are the results of 2.4.10-pre14aa1 + your patch:

Elapsed (wall clock) time (h:mm:ss or m:ss): 5:23.55
Elapsed (wall clock) time (h:mm:ss or m:ss): 5:32.21
Elapsed (wall clock) time (h:mm:ss or m:ss): 5:34.77
Elapsed (wall clock) time (h:mm:ss or m:ss): 6:17.55
Elapsed (wall clock) time (h:mm:ss or m:ss): 5:49.31

Is the performance fix also required for 2.4.9-acXX ?

Regards,

   Jogi

-- 

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