On Tue, 6 Dec 2005, Steinar H. Gunderson wrote:
On Tue, Dec 06, 2005 at 01:40:47PM +0300, Olleg wrote:
I can't undestand why "bigger is better". For instance in search by
index. Index point to page and I need load page to get one row. Thus I
load 8kb from disk for every raw. And keep it then in
On Tue, Dec 06, 2005 at 01:40:47PM +0300, Olleg wrote:
> I can't undestand why "bigger is better". For instance in search by
> index. Index point to page and I need load page to get one row. Thus I
> load 8kb from disk for every raw. And keep it then in cache. You
> recommend 64kb. With your rec
Ron wrote:
In general, and in a very fuzzy sense, "bigger is better". pg files are
laid down in 1GB chunks, so there's probably one limitation.
Hm, expect result of tests on other platforms, but if there theoretical
dispute...
I can't undestand why "bigger is better". For instance in search b
Ron <[EMAIL PROTECTED]> writes:
> Where? BLCKSZ as large as 64KB has been shown to improve
> performance.
Not in the Postgres context, because you can't set BLCKSZ higher than
32K without doing extensive surgery on the page item pointer layout.
If anyone's actually gone to that much trouble, the
At 04:32 PM 12/5/2005, Olleg wrote:
Tom Lane wrote:
Olleg Samoylov <[EMAIL PROTECTED]> writes:
I try to test this. Linux, memory page 4kb, disk page 4kb. I set
BLCKSZ to 4kb. I get some performance improve, but not big, may be
because I have 4Gb on test server (amd64).
It's highly unlikely th
Olleg wrote:
> I test performace on database test server. This is copy of working
> billing system to test new features and experiments. Test task was one
> day traffic log. Average time of a one test was 260 minutes. Postgresql
> 7.4.8. Server dual Opteron 240, 4Gb RAM.
Did you execute querie
Tom Lane wrote:
Olleg Samoylov <[EMAIL PROTECTED]> writes:
I try to test this. Linux, memory page 4kb, disk page 4kb. I set BLCKSZ
to 4kb. I get some performance improve, but not big, may be because I
have 4Gb on test server (amd64).
It's highly unlikely that reducing BLCKSZ is a good idea.
Olleg Samoylov <[EMAIL PROTECTED]> writes:
> I try to test this. Linux, memory page 4kb, disk page 4kb. I set BLCKSZ
> to 4kb. I get some performance improve, but not big, may be because I
> have 4Gb on test server (amd64).
It's highly unlikely that reducing BLCKSZ is a good idea. There are bad
src/include/pg_config_manual.h define BLCKSZ 8196 (8kb).
Somewhere I readed BLCKSZ must be equal to memory page of operational
system. And default BLCKSZ 8kb because first OS where postgres was build
has memory page size 8kb.
I try to test this. Linux, memory page 4kb, disk page 4kb. I set BL
