Re: Speedup patch for 2.4.19-pre6 in bitmap.c

[Philippe Gramoulle <philippe.gramoulle@mmania.com>]

On Wed, Apr 10, 2002 at 07:13:56PM +0400, Oleg Drokin wrote:
> Hello!
> 
> On Wed, Apr 10, 2002 at 05:09:19PM +0200, Philippe Gramoulle wrote:
> 
> > > So I assume you are negatively surprised, right?
> > > And if you undo the speedup patch only, do you get your numbers back?
> > > Also do you have highmem on for 2.4.19-pre6 kernel?
> > Sorry for the confusion :
> > With 2.4.18 + TCP patch => 10Mb/s
> > Now witout the speedup patch and with a 2.4.19-pre6 + the patches i've listed => 6.32 Mb/s NFS TCP
> 
> > That's why i want to give your speedup patch a try !! :o)
> 
> Ah. So my question remains, do you have highmem enabled? If you do,
> also try without highmem with and without speedup patches.

Yep , i forgot to answer your question :-(

Yes Higmem is enabled.

As you suggested, i'll try with and without the speedup patch as well as with and
without Highmem.

> Number of peoples raised a question about Andrea Archangelli's patch
> that went into 2.4.19-pre5 to improve I/O throughtput wrt several allocation
> zones.
> I myself see throughtput decrease with highmem on.

As a reminder here is the test with no speedup patch and Highmem on:
time dd if=/dev/zero of=test1 bs=8192 count=25000
25000+0 records in
25000+0 records out

real    0m32.182s
user    0m0.020s
sys     0m1.530s

Now with the speedup patch and still highmem on:

time dd if=/dev/zero of=test2 bs=8192 count=25000
25000+0 records in
25000+0 records out

real    0m41.149s
user    0m0.000s
sys     0m0.920s

With the speedup patch and highmem off:

time dd if=/dev/zero of=zobada bs=8192 count=25000
e25000+0 records in             
25000+0 records out             
                                
real    0m40.390s               
user    0m0.020s                
sys     0m1.070s              

I'll send the missing test ( without speedup patch and without Highmem) later tonight.

Thanks,

Philippe.

PS: i'll also redo some tests with 2.4.18 +NFS_ALL and try with UDP as well.