The lost art of benchmarking was Re: Reiser4

[Jonathan Corbet]

Jean Francois Martinez <jfm512 at free.fr> wrote:

> First of all it looks like the guy divided his 4GB disk in two 2G
> partitions and installed Reiser on one partition and EXT3 in the
> other.  WRONG!  Modern disks have more sectors in the outer, 
> lower numbered tracks. Meaning that you will get higher throughput 
> from hda1 than from hda2.

Wrong indeed.  The same partition was used for all tests.  One can give
me a little credit, even if it hurts.

> He also compiled the kernel as a benchmark.  99% of times this is the
> touchstone for lack of proper thinking in benchmarking.  

Because I benchmarked an actual task that my readers are likely to
perform?  

Look, the benchmarks in the LWN articles were a low-value exercise, just
to get a rough feel for the performance benefits claimed by reiser4.  I
believe I succeeded in that goal.  Among other things, I turned up the
fact that, if you fail to create your files in the right order,
performance suffers significantly - something which the Namesys
marketing literature somehow failed to mention.

jon

Jonathan Corbet
Executive editor, LWN.net
corbet at lwn.net