BLCKSZ

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 BLCKSZ
to 4kb. I get some performance improve, but not big, may be because I
have 4Gb on test server (amd64).

Can anyone test it also? May be better move BLCKSZ from
pg_config_manual.h to pg_config.h?

--
Olleg Samoylov