Re: [PERFORM] reducing random_page_cost from 4 to 2 to force index scan

2011-05-14 Thread Stuart Bishop
On Sat, May 14, 2011 at 3:13 AM, Josh Berkus wrote: > This is what the combination of random_page_cost and > effective_cache_size ought to supply, but I don't think it does, quite. I think random_page_cost causes problems because I need to combine disk random access time, which I can measure, wi

Re: [PERFORM] Using pgiosim realistically

2011-05-14 Thread k...@rice.edu
On Fri, May 13, 2011 at 09:09:41PM +, John Rouillard wrote: > Hi all: > > I am adding pgiosim to our testing for new database hardware and I am > seeing something I don't quite get and I think it's because I am using > pgiosim incorrectly. > > Specs: > > OS: centos 5.5 kernel: 2.6.18-194.3

[PERFORM] KVP table vs. hstore - hstore performance (Was: Postgres NoSQL emulation)

2011-05-14 Thread Stefan Keller
Hi, I am conducting a benchmark to compare KVP table vs. hstore and got bad hstore performance results when the no. of records is greater than about 500'000. CREATE TABLE kvp ( id SERIAL PRIMARY KEY, key text NOT NULL, value text ); -- with index on key CREATE TABLE myhstore ( id SERIAL PRIMARY K