Re: [PERFORM] Index on a NULL-value

2005-05-31 Thread Tobias Brox
CREATE INDEX b_is_null ON mock(a) WHERE b IS NULL; where a is chosen as a column that you frequently also test in conjunction with b IS NULL. That is, the above index can efficiently handle queries like ... WHERE a = 42 AND b IS NULL ... This is wonderful, it seems like most of

[PERFORM] very large table

2005-05-31 Thread Praveen Raja
Hi Im trying to move an existing solution from MySQL to PostgreSQL. As it is now the solution has 4 tables where data in inserted by an application. At regular intervals (10min) data from these tables is consolidated and moved to another table for reporting purposes. There exist many

[PERFORM] SURVEY: who is running postgresql on 8 or more CPUs?

2005-05-31 Thread Dirk Lutzeb├Ąck
Hi, I would like to start a little survey who is running postgresql on an 8way or more machine (Intel, Sparc, AMD no matter). Purpose: find out how postgresql runs in high performance areas. Please fillout: Machine (Vendor, Product): Architecture (Intel/Sparc/AMD/IBM): Processors

Re: [PERFORM] slow queries, possibly disk io

2005-05-31 Thread Josh Close
I didn't see iostat as available to install, but I'm using dstat to see this. The server has constant disk reads averaging around 50M and quite a few in the 60M range. This is when selects are being done, which is almost always. I would think if postgres is grabbing everything from memory that

Re: [PERFORM] very large table

2005-05-31 Thread Tom Lane
Praveen Raja [EMAIL PROTECTED] writes: I'm trying to move an existing solution from MySQL to PostgreSQL. As it is now the solution has 4 tables where data in inserted by an application. At regular intervals (10min) data from these tables is consolidated and moved to another table for reporting

Re: [PERFORM] slow queries, possibly disk io

2005-05-31 Thread Tom Lane
Josh Close [EMAIL PROTECTED] writes: There is 2 gigs of mem in this server. Here are my current settings. max_connections = 100 shared_buffers = 5 sort_mem = 4096 vacuum_mem = 32768 effective_cache_size = 45 Shared buffers is set to 10% of total mem. Effective cache size is 90% of

Re: [PERFORM] slow queries, possibly disk io

2005-05-31 Thread Josh Close
On 5/31/05, Martin Fandel [EMAIL PROTECTED] wrote: In the documentation of http://www.powerpostgresql.com/Downloads/annotated_conf_80.html is the shared_buffers set to 1/3 of the availble RAM. You're set 5*8/1024=391 MB SHMEM. The effective_cache_size in your configuration is

[PERFORM] 'Fastest' PC's are slowest in the house

2005-05-31 Thread Justin Davis
I have five PC's accessinga PG database that is mounted on a DellWindows 2003 server. The PC's are accessing the database with a Fujitsu cobol program via ODBC (all machines have same (newest)ODBC driver from PG).2 of the machines are the newest I have andboth pretty identically configured

Re: [PERFORM] slow queries, possibly disk io

2005-05-31 Thread Manfred Koizar
On 5/31/05, Martin Fandel [EMAIL PROTECTED] wrote: In the documentation of http://www.powerpostgresql.com/Downloads/annotated_conf_80.html is the shared_buffers set to 1/3 of the availble RAM. Well, it says you should never use more than 1/3 of your available RAM which is not quite the same as

Re: [PERFORM] postgresql-8.0.1 performance tuning

2005-05-31 Thread John A Meinel
Martin Fandel wrote: Hi @ all, i'm trying to tune my postgresql-db but i don't know if the values are right set. I use the following environment for the postgres-db: # Hardware cpu: 2x P4 3Ghz ram: 1024MB DDR 266Mhz partitions: /dev/sda3 23G 9,6G 13G

[PERFORM] Major flood of mail to lists ...

2005-05-31 Thread Marc G. Fournier
Do to moderator error (namely, mine), several hundred messages (spread across all the lists) were just approved ... Sorry for all the incoming junk :( Marc G. Fournier Hub.Org Networking Services (http://www.hub.org) Email: [EMAIL PROTECTED] Yahoo!: yscrappy

Re: [PERFORM] postgresql-8.0.1 performance tuning

2005-05-31 Thread Cosimo Streppone
Martin Fandel wrote: i'm trying to tune my postgresql-db but i don't know if the values are I use the following environment for the postgres-db: I assumed you're running Linux here, you don't mention it. # Hardware cpu: 2x P4 3Ghz ram: 1024MB DDR 266Mhz I think 1Gb

Re: [PERFORM] Index on a NULL-value

2005-05-31 Thread Tobias Brox
[Tobias Brox - Tue at 11:02:07AM +0800] I read in the manual today: Indexes are not used for IS NULL clauses by default. The best way to use indexes in such cases is to create a partial index using an IS NULL predicate. I have summarized this thread in a postgresql doc user comment,