Re: [PERFORM] database tuning

2007-12-07 Thread Richard Huxton
kelvan wrote: hi i need to know all the database overhead sizes and block header sizes etc etc as I have a very complex database to build and it needs to be speed tuned beyond reckoning [snip] I am using postgres 8.1 if anyone can post links to pages containing over head information and

Re: [PERFORM] Trouble with LEFT JOIN using VIEWS.

2007-12-07 Thread Tom Lane
=?ISO-8859-2?Q?Piotr_Gasid=B3o?= [EMAIL PROTECTED] writes: I've just hit problem, that is unusual for me. View definition: SELECT users.id, users.user_name, users.extra IS NOT NULL AS has_extra FROM users; What you've got here is a non-nullable target list, which creates an

[PERFORM] Trouble with LEFT JOIN using VIEWS.

2007-12-07 Thread Piotr Gasidło
Hello, I've just hit problem, that is unusual for me. quaker= \d sites Table public.sites Column | Type| Modifiers ---+---+ id| integer

[PERFORM] Cost-Based Vacuum Delay tuning

2007-12-07 Thread Guillaume Cottenceau
Hi, I'm currently trying to tune the Cost-Based Vacuum Delay in a 8.2.5 server. The aim is to reduce as much as possible the performance impact of vacuums on application queries, with the background idea of running autovacuum as much as possible[1]. My test involves vacuuming a large table, and

Re: [PERFORM] database tuning

2007-12-07 Thread Simon Riggs
On Fri, 2007-12-07 at 12:45 +1200, kelvan wrote: hi i need to know all the database overhead sizes and block header sizes etc etc as I have a very complex database to build and it needs to be speed tuned beyond reckoning If your need-for-speed is so high, I would suggest using 8.3 or at

Re: [PERFORM] Cost-Based Vacuum Delay tuning

2007-12-07 Thread Erik Jones
On Dec 7, 2007, at 4:50 AM, Guillaume Cottenceau wrote: Hi, I'm currently trying to tune the Cost-Based Vacuum Delay in a 8.2.5 server. The aim is to reduce as much as possible the performance impact of vacuums on application queries, with the background idea of running autovacuum as much as

Re: [PERFORM] TB-sized databases

2007-12-07 Thread Robert Treat
On Thursday 06 December 2007 04:38, Simon Riggs wrote: Robert, On Wed, 2007-12-05 at 15:07 -0500, Robert Treat wrote: If the whole performance of your system depends upon indexed access, then maybe you need a database that gives you a way to force index access at the query level? That

Re: [PERFORM] database tuning

2007-12-07 Thread kelvan
Simon Riggs [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] On Fri, 2007-12-07 at 12:45 +1200, kelvan wrote: hi i need to know all the database overhead sizes and block header sizes etc etc as I have a very complex database to build and it needs to be speed tuned beyond

[PERFORM] Measuring table and index bloat

2007-12-07 Thread Greg Smith
One of those things that comes up regularly on this list in particular are people whose performance issues relate to bloated tables or indexes. What I've always found curious is that I've never seen a good way suggested to actually measure said bloat in any useful numeric terms--until today.

Re: [PERFORM] TB-sized databases

2007-12-07 Thread Ron Mayer
Tom Lane wrote: Ron Mayer [EMAIL PROTECTED] writes: Tom Lane wrote: There's something fishy about this --- given that that plan has a lower cost estimate, it should've picked it without any artificial constraints. One final thing I find curious about this is that the estimated number of rows

Re: [PERFORM] Cost-Based Vacuum Delay tuning

2007-12-07 Thread Erik Jones
On Dec 7, 2007, at 10:44 AM, Guillaume Cottenceau wrote: Erik Jones erik 'at' myemma.com writes: vacuum_cost_delay/vacuum_cost_limit (deactivated) 20/200 40/200 100/1000 150/1000 200/1000 300/1000 VACUUM ANALYZE time54 s112 s188 s109 s

Re: [PERFORM] Cost-Based Vacuum Delay tuning

2007-12-07 Thread Guillaume Cottenceau
Erik Jones erik 'at' myemma.com writes: vacuum_cost_delay/vacuum_cost_limit (deactivated) 20/200 40/200 100/1000 150/1000 200/1000 300/1000 VACUUM ANALYZE time54 s112 s188 s109 s 152 s 190 s 274 s SELECT time