[PERFORM] Re: GROUP BY with reasonable timings in PLAN but unreasonable execution time

2011-07-07 Thread Clem Dickey
On 07/05/2011 07:26 PM, Clem Dickey wrote: Updates after belatedly reading the slow queries guidelines: Version: PostgreSQL 8.4.8 on x86_64-redhat-linux-gnu, compiled by GCC gcc (GCC) 4.4.5 20101112 (Red Hat 4.4.5-2), 64-bit The query has always been slow; the table for this test case is

Re: [PERFORM] 100% CPU Utilization when we run queries.

2011-07-07 Thread Robert Klemme
On Wed, Jul 6, 2011 at 9:04 PM, Tomas Vondra t...@fuzzy.cz wrote: Dne 6.7.2011 15:30, bakkiya napsal(a): Any help, please? According to the EXPLAIN ANALYZE output (please, don't post it to the mailing list directly - use something like explain.depesz.com, I've done that for you this time:

Re: [PERFORM] 100% CPU Utilization when we run queries.

2011-07-07 Thread bakkiya
Thanks all for your help. It is really useful, I will modify the query and post the result. -- View this message in context: http://postgresql.1045698.n5.nabble.com/100-CPU-Utilization-when-we-run-queries-tp4465765p4560941.html Sent from the PostgreSQL - performance mailing list archive at

[PERFORM] DELETE taking too much memory

2011-07-07 Thread vincent dephily
Hi, I have a delete query taking 7.2G of ram (and counting) but I do not understant why so much memory is necessary. The server has 12G, and I'm afraid it'll go into swap. Using postgres 8.3.14. I'm purging some old data from table t1, which should cascade-delete referencing rows in t2. Here's

[PERFORM] very large record sizes and ressource usage

2011-07-07 Thread jtkells
Is there any guidelines to sizing work_mem, shared_bufferes and other configuration parameters etc., with regards to very large records? I have a table that has a bytea column and I am told that some of these columns contain over 400MB of data. I am having a problem on several servers reading

Re: [PERFORM] [GENERAL] DELETE taking too much memory

2011-07-07 Thread Guillaume Lelarge
On Thu, 2011-07-07 at 15:34 +0200, vincent dephily wrote: Hi, I have a delete query taking 7.2G of ram (and counting) but I do not understant why so much memory is necessary. The server has 12G, and I'm afraid it'll go into swap. Using postgres 8.3.14. I'm purging some old data from table

[PERFORM] VACUUM FULL ANALYZE vs. Autovacuum Contention

2011-07-07 Thread D C
Hello, (Apologies for any possible duplication of this email.) (Also, apologies if this is an obvious question. I have gone through the archives without seeing something that directly ties to this.) We are running Postgresql on a 64b RHEL5.2 64b server. Uname -a: --Linux xxx

Re: [PERFORM] VACUUM FULL ANALYZE vs. Autovacuum Contention

2011-07-07 Thread Scott Marlowe
On Thu, Jul 7, 2011 at 2:30 PM, D C ptrading...@gmail.com wrote: Hello, (Apologies for any possible duplication of this email.) (Also, apologies if this is an obvious question.  I have gone through the archives without seeing something that directly ties to this.) We are running Postgresql

Re: [PERFORM] VACUUM FULL ANALYZE vs. Autovacuum Contention

2011-07-07 Thread Greg Smith
On 07/07/2011 04:30 PM, D C wrote: autovacuum_naptime = 30s autovacuum_vacuum_threshold = 200 autovacuum_vacuum_scale_factor = 0.5 autovacuum_vacuum_cost_delay = 10 These are slightly strange settings. How did you come up with them? The autovacuum_vacuum_scale_factor being so high is