Re: Has anybody think about changing BLCKSZ to an option of initdb?

Tom Lane wrote:
> Gregory Stark <stark@enterprisedb.com> writes:
>> So has anyone here done any experiments with live systems with different block
>> sizes? What were your experiences? 

Mark tested this back in the OSDL days.  His findings on DBT2 was that 
the right *combination* of OS and PG blocksizes gave up to a 5% 
performance increase, I think.  Hardly enough to make it worth the 
headache of running with non-default PG and non-deafault Linux block 
sizes, especially since the wrong combination resulted in a decrease in 
performance, sometimes dramatically so.

However, at Greenplum I remember determining that larger PG block sizes, 
if matched with larger filesystem block sizes did significantly help on 
performance of data warehouses which do a lot of seq scans -- but that 
our ceiling of 32K was still too small to really make this work.  I 
don't have the figures for that, though; Luke reading this?

--Josh