Re: HEADS UP - HAMMER work

["Dennis Melentyev" <dennis.melentyev@xxxxxxxxx>]

2008/11/15 Michael Neumann <mneumann@ntecs.de>:
> Dennis Melentyev schrieb:
>>
. ..
>>
>> Sysctl/some-other-tunable with some kind of mask would be great for
>> fine-tuning (and just useless for the 90% of users).
>>
>> like:
>> sysctl.hammer.dirhash.hashmask.prefix=1 (Starting at first filename
>> byte, 3 bytes fixed length)
>> sysctl.hammer.dirhash.hashmask.suffix=-1 (Starting last byte, 2 bytes
>> length)
>
> Hm, but the hash is stored on-disk within each b-tree node, so changing the
> hash-function becomes pretty dangerous!

That could be done via an option upon PFS creation, changed with
"hammer" utility parameter, whatever else way. As I wrote:
"sysctl/some-other-tunable".
Anyway, for me, it is fine tuning issue. Quite rare and very special
one. I hardly see any need in such thing for 99% of installations, but
there sure are cases when it is a huge plus.

-- 
Dennis Melentyev