Re: Bumping block size to 16K on FreeBSD... - Mailing list pgsql-hackers

From Neil Conway
Subject Re: Bumping block size to 16K on FreeBSD...
Date
Msg-id 20030829023547.GI63737@home.samurai.com
Whole thread Raw
In response to Re: Bumping block size to 16K on FreeBSD...  (Sean Chittenden <sean@chittenden.org>)
Responses Re: Bumping block size to 16K on FreeBSD...
List pgsql-hackers
On Thu, Aug 28, 2003 at 01:00:44PM -0700, Sean Chittenden wrote:
> Other than you feeling uneasy about the possibility of uncovering bugs
> because this hasn't been widely done like this before, do you have any
> other concerns, or do you think the possibility of finding bugs very
> likely?

In case Tom didn't make this clear, I'm strongly opposed to making
this change without doing the necessary (non-FreeBSD-specific) legwork.
The bottom-line is that if we're going to be changing the block size
on a regular basis, it needs to be completely transparent to the user,
from a functionality perspective. That's currently not the case:
changing the BLCKSZ changes the meaning of shared_buffers and
effective_cache_size, for example, so tuning documents written for
other operating systems won't apply as easily to PostgreSQL on
FreeBSD. Until the user-visible effects of BLCKSZ have been ironed
over[1], I definately think you shouldn't include the patch in the
FreeBSD port.

[1] - Other improvements, like making it easier to change the     blocksize (making it a configure option?) would be
cooltoo.
 

-Neil



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