Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-08-14 Thread Tom Lane
Sean Chittenden [EMAIL PROTECTED] writes: If you CLUSTER on an index and then ANALYSE, you get a correlation of 1.0 (== optimum) for the first column of the index. Correlating of what to what? Of data to nearby data? Of data to related data (ie, multi-column index?)? Of related data to

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-08-09 Thread Sean Chittenden
I have an experimental patch lying around somewhere that tries to work around these problems by offering different estimation methods for index scans. If you are interested, I'll dig it out. Sure, I'll take a gander... had my head in enough Knuth recently to even hopefully have some

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-08-05 Thread Sean Chittenden
is some other problem that needs to be solved. (I'd wonder about index correlation myself; we know that that equation is pretty bogus.) Could be. I had him create a multi-column index on the date and a non-unique highly redundant id. Tom has already suspected index correlation to be

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-20 Thread Bruce Momjian
Michael Pohl wrote: On Sun, 6 Jul 2003, Matthew Nuzum wrote: At the very least, if there is good documentation for these parameters, maybe the conf file should provide a link to this info. I believe that is what Josh is proposing:

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-09 Thread Kaarel
Are you willing to say that the PostgreSQL database system should only be used by DBAs? I believe that Postgres is such a good and useful tool that anyone should be able to start using it with little or no barrier to entry. I quite agree. But there is a difference between saying you should get

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-09 Thread scott.marlowe
On Wed, 9 Jul 2003, Kaarel wrote: Are you willing to say that the PostgreSQL database system should only be used by DBAs? I believe that Postgres is such a good and useful tool that anyone should be able to start using it with little or no barrier to entry. I quite agree. But there

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-09 Thread Martin Foster
Scott Marlowe wrote: It would be nice to have a program that could run on any OS postgresql runs on and could report on the current limits of the kernel, and make recommendations for changes the admin might want to make. One could probably make a good stab at effective cache size during

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-09 Thread Sean Chittenden
I don't have much to add because I'm pretty new to Postgres and have been soliciting advice here recently, but I totally agree with everything you said. I don't mind if it's in the postgres.conf file or in a faq that is easy to find, I just would like it to be in one place. A good example

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-09 Thread Martin Foster
Sean Chittenden wrote: I looked through the src/doc/runtime.sgml for a good place to stick this and couldn't find a place that this seemed appropriate, but on FreeBSD, this can be determined with a great deal of precision in a programmatic manner: echo effective_cache_size = $((`sysctl -n

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-07 Thread Chris Travers
Matthew Nuzum wrote: I'm highly resistant to/disappointed in this attitude and firmly believe that there are well understood algorithms that DBAs use to diagnose and solve performance problems. It's only a black art because it hasn't been documented. Performance tuning isn't voodoo, it's

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-06 Thread Matthew Nuzum
Brian Suggests: I'm curious how many of the configuration values can be determined automatically, or with the help of some script. It seem like there could be some perl script in contrib that could help figure this out. Possibly you are asked a bunch of questions and then the values

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-06 Thread Michael Pohl
On Sun, 6 Jul 2003, Matthew Nuzum wrote: At the very least, if there is good documentation for these parameters, maybe the conf file should provide a link to this info. I believe that is what Josh is proposing: http://archives.postgresql.org/pgsql-performance/2003-07/msg00102.php [Apache

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-06 Thread Martin Foster
Michael Pohl wrote: On Sun, 6 Jul 2003, Matthew Nuzum wrote: At the very least, if there is good documentation for these parameters, maybe the conf file should provide a link to this info. I believe that is what Josh is proposing:

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-03 Thread scott.marlowe
On Thu, 3 Jul 2003, Sean Chittenden wrote: What are the odds of going through and revamping some of the tunables in postgresql.conf for the 7.4 release? I was just working with someone on IRC and on their 7800 RPM IDE drives, their random_page_cost was ideally suited to be 0.32: a far cry

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-03 Thread Michael Mattox
I don't have much to add because I'm pretty new to Postgres and have been soliciting advice here recently, but I totally agree with everything you said. I don't mind if it's in the postgres.conf file or in a faq that is easy to find, I just would like it to be in one place. A good example of the

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-03 Thread Ron
Hear, hear! Well said Sean. I know that there has been disagreement about this in the past (recommending settings, with some very good reasons), however as a programmer/part-time DBA, something like this would be extremely useful. Our company recently developed a web-based app for a client who

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-03 Thread Tom Lane
Sean Chittenden [EMAIL PROTECTED] writes: What are the odds of going through and revamping some of the tunables in postgresql.conf for the 7.4 release? I was arguing awhile back for bumping the default shared_buffers up, but the discussion trailed off with no real resolution. I was just

Re: [PERFORM] Moving postgresql.conf tunables into 2003...

2003-07-03 Thread Brian Hirt
I'm curious how many of the configuration values can be determined automatically, or with the help of some script. It seem like there could be some perl script in contrib that could help figure this out. Possibly you are asked a bunch of questions and then the values are computed based on