Re: Hugetables question

On Wed, Jun 22, 2011 at 02:31:01PM +0200, Rados??aw Smogura wrote:
> I strictly disagree with opinion if there is 1% it's worthless. 1%
> here, 1% there, and finally You get 10%, but of course hugepages
> will work quite well if will be used in code that require many
> random "jumps". I think this can be reproduced and some not-common
> case may be found to get performance of about 10% (maybe upload
> whole table in shared buffer and randomly "peek" records one by
> one).

I think the point is not that 1% is worthless, but that it hasn't been
shown that it is a 1% improvement, becuase the noise is too large.

For benefits this small, what you need to is run each test 100 times
and check the mean and standard deviation and see whether the
improvment is real or not.

When the benefit is 10% you only need a handful of runs to prove it,
which is why they're accepted easier.

Have a nice day,
--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> Patriotism is when love of your own people comes first; nationalism,
> when hate for people other than your own comes first.
> - Charles de Gaulle