Re: [PATCH] (1/2) reverse mapping VM for 2.5.23 (rmap-13b)

[rwhron@earthlink.net]

> Maybe Randy Hron (added to Cc) can find some spare time
> to benchmark these sometime before the summit too[1]. 

dbench isn't scaling as well with the -rmap13b patch.
With 128 processes, dbench throughput is less than 1/3
of mainline.

dbench ext2 32 processes   Average     High        Low
2.5.24                      28.24     28.84      27.30 mb/sec
2.5.24-rmap13b              21.64     23.50      19.71

dbench ext2 128 processes  Average     High        Low
2.5.24                      19.32     21.05      18.05
2.5.24-rmap13b               5.34      5.38       5.30

tiobench:
Sequential reads, rmap had about 10% more throughput 
and lower max latency.  
For random reads, throughput was lower and max latency 
was higher with rmap.  

Lmbench:
Most metrics look better with rmap.  Exceptions
are fork/exec latency and mmap latency.  mmap
latency was 18% higher with rmap.

Autoconf build (fork test) was about 5% faster
without rmap.

Details at:
http://home.earthlink.net/~rwhron/kernel/latest.html

-- 
Randy Hron