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.  There are bad
side-effects on the maximum index entry size, maximum number of tuple
fields, etc.

Yes, when I set BLCKSZ=512, database dont' work. With BLCKSZ=1024 database very slow. (This was surprise me. I expect increase performance in 8 times with 1024 BLCKSZ. :) ) As I already see in this maillist, increase of BLCKSZ reduce performace too. May be exist optimum value? Theoretically BLCKSZ equal memory/disk page/block size may reduce defragmentation drawback of memory and disk.

In any case, when you didn't say *what* you tested, it's
impossible to judge the usefulness of the change.
                        regards, tom lane

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.

--
Olleg

---------------------------(end of broadcast)---------------------------
TIP 2: Don't 'kill -9' the postmaster

Reply via email to