[ADMIN] Option shared_buffers in PostgreSQL

2011-05-01 Thread Javier Reyes
Hello. I have a server with 4GB of RAM and PostgreSQL 9.0.3 on Centos 5. I'm using pgbench and pgbench-tools to measure performance, using two pgbench-tools queries: select and tpc-b. With default settings of postgresql.conf and select query, I get the following results: Scale: 1, 10, 100, 1000.

Re: [ADMIN] Option shared_buffers in PostgreSQL

2011-05-01 Thread Lou Picciano
Javier, There has been much discussion of this. Generally - and though it's a bit counter-intuitive - wholesale increase in PostgreSQL's shared buffer won't give you the outcomes you might expect. In short, once there's enough, there's enough. Workmem is another option which behaves along

Re: [ADMIN] Option shared_buffers in PostgreSQL

2011-05-01 Thread Tom Lane
Javier Reyes writes: > I have a server with 4GB of RAM and PostgreSQL 9.0.3 on Centos 5. I'm using > pgbench and pgbench-tools to measure performance, using two pgbench-tools > queries: select and tpc-b. > With default settings of postgresql.conf and select query, I get the > following results:

Re: [ADMIN] Re: best practice for moving millions of rows to child table when setting up partitioning?

2011-05-01 Thread Greg Smith
On 04/27/2011 03:35 PM, Mark Stosberg wrote: In particular, I wanted to check whether the UPDATE statement would alter all the rows automatically, or if the underlying trigger would cause all the rows processed a row at a time. It appears from my test that the result of the UPDATE was going to a

Re: [ADMIN] archive_timeout behavior (8.4.6)

2011-05-01 Thread Greg Smith
On 04/22/2011 08:23 PM, Brian Fehrle wrote: So long story short, if a cluster has zero activity, and archive_timeout is not set to 0, when it reaches that timeout should it generate a file, or just skip because it would be 100% empty? You're right about what you've seen here, there is some log