Re: [Benchmark] AIM9 results

Hans Reiser
2002-12-23T07:05:27Z

Cliff White wrote:

>>Andrew Morton wrote:
>>
>>
>>
>>>Andrew Morton wrote:
>>>
>>>
>>>
>>>
>>>>Hans Reiser wrote:
>>>>
>>>>
>>>>
>>>>
>>>>>Andrew and Chris, are these changes in performance definitely due to VM
>>>>>changes (and not some difference I am not thinking of between 2.5 and
>>>>>2.4 reiserfs code)?
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>aim9 is just doing
>>>>
>>>> for (lots)
>>>> close(creat(filename))
>>>>
>>>>
>>>>
>>>>
>>> unlink(filename); /* of course */
>>>
>>>
>>>
>>>
>>>
>>>
>>Oh, commercial fs vendors must really love tuning for this benchmark....
>>sigh....
>>
>>
>>
>Ya, we think the AIM stuff is getting a little old. The basic idea is fine, but
>many of the tests do _very little work. We (OSDL) would like to re-do
>AIM9+7 and make it more useful. We'd love to have some input from everyone....
>For example, how big a file should we create for a real creat() test ?
>cliffw
>
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>
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>
Well, if you take a look at mongo.pl available at www.namesys.com we
provide you with a fractal file size generation program that you might
want to look at, that mongo uses during the creation portion of its
benchmark.

It makes 80% of the files less than some amount (100 bytes, or 1k, or
4k, depending on how mean you want to be to ext2;-) ), then 80% of the
remaining 20% less than 10 times that amount then....

There is more than one version of the file size generation code, so make
sure you got the one that works as I described above. I am looking for
a formula to smooth the above behavior into some sort of gentle curve
rather than sharp bands, but I haven't found it yet.

Hans