Michael Widenius wrote:
>
> >>>>> "matthew" == matthew mcglynn <mcglynn@stripped> writes:
>
> matthew> This is probably a really dumb question...
>
> matthew> Every example of buffer settings I've seen
> matthew> has used powers of two. For example, from the
> matthew> sample configuration file:
> matthew> set-variable = key_buffer=16M
> matthew> set-variable = max_allowed_packet=1M
> matthew> set-variable = thread_stack=128K
> matthew> set-variable = max_allowed_packet=16M
> matthew> set-variable = keybuffer=16M
>
> matthew> Similarly, the default table_cache is 64, and when
> matthew> people ask on this list about running out of file
> matthew> descriptors, the response is usually "set table_cache
> matthew> to 32".
>
> matthew> My dumb question is: do these have to all be powers of two ?!
>
> matthew> If for my application, a table_cache of 128 is insufficient,
> matthew> can I bump it to 150 or do I need to go all the way to 256 ?
>
> Hi!
>
> I just prefer to use powers as two as this gives you the best memory
> utilization with many memory allocation packages!
>
> You don't however have to use powers of two; For the table cache 150
> should be fine!
>
> Regards,
> Monty
>
And to add to what Monty has said, powers of 2 are
"holy" numbers for a programmer, just like powers of 10
are "holy" for non-programmers.
--
Sasha Pachev
http://www.sashanet.com/ (home)
http://www.direct1.com/ (work)