Re: [PERFORM] Configuring for maximum memory usage

Hi, you could set effective_cache_size to a high value (free memory on your server that is used for caching). Christiaan Willemsen wrote: Hi there, I configured OpenSolaris on our OpenSolaris Machine. Specs: 2x Quad 2.6 Ghz Xeon 64 GB of memory 16x 15k5 SAS The filesystem is configured

[PERFORM] More shared_buffers instead of effective_cache_size?

, 30.1 MB/s That is really really slow (10 times slower than on my other machine). What would you do now? Increasing shared_buffers to 100MB and setting effective_cache_size to 0MB? Or increasing effective_cache_size, too? Thanks for help. Regards, -Ulrich -- Sent via pgsql-performance mailing

Re: [PERFORM] More shared_buffers instead of effective_cache_size?

query which will never return more than 500 rows. -Ulrich -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance

Re: [PERFORM] More shared_buffers instead of effective_cache_size?

Scott Marlowe wrote: On Thu, Sep 4, 2008 at 1:39 PM, Ulrich [EMAIL PROTECTED] wrote: I wouldn't set shared_buffers that high just because things like vacuum and sorts need memory too Okay, I understand that vacuum uses memory, but I thought sorts are done in work_mem? I am only

Re: [PERFORM] Subquery WHERE IN or WHERE EXISTS faster?

with 256MB RAM and the webserver also likes to use some RAM. Does Postgre cache the HASH-Table for later use? For example when the user reloads the website. Kind regards Ulrich Rusty Conover wrote: This is what I've found with tables ranging in the millions of rows. Using IN is better when

Re: [PERFORM] Subquery WHERE IN or WHERE EXISTS faster?

..113.75 rows=8 width=5) (actual time=0.321..0.328 rows=13 loops=1) It looks like if this row is something like min(max_rows=13, LIMIT+OFFSET). But I do not completely understand the Syntax... ;-) Kind regards Ulrich Gregory Stark wrote: Ulrich [EMAIL PROTECTED] writes: EXPLAIN ANALYZE

Re: [PERFORM] Subquery WHERE IN or WHERE EXISTS faster?

0.478ms if I use query #1. Kind Regards, Ulrich Tom Lane wrote: Ulrich [EMAIL PROTECTED] writes: People say that [EXISTS is faster] People who say that are not reliable authorities, at least as far as Postgres is concerned. But it is always a bad idea to extrapolate results on toy

Re: [PERFORM] Large objetcs performance

everything to a linux machine. Ulrich ---(end of broadcast)--- TIP 4: Have you searched our list archives? http://archives.postgresql.org

Re: [PERFORM] Large objetcs performance

everything to a linux machine. Ulrich

[PERFORM] query planner: automatic rescribe of LIKE to BETWEEN ?

Hello all, had an idea of optimizing a query that may work generally. In case a 'column' is indexed, following two alterations could be done I think: A) select ... where column ~ '^Foo' -- Seq Scan into that: select ... where column BETWEEN 'Foo' AND 'FooZ' -- Index Scan of

Re: [PERFORM] How to determine cause of performance problem?

. /Ulrich ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match

[PERFORM] Need for speed 3

ways to do it? Is there some literature you recommend reading? TIA Ulrich ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings

Re: [PERFORM] Need for speed 3

executes advanced query interface call to the server. How would that improve performance? Ulrich ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq

[PERFORM] Need for speed 2

queries with less data (at the same time) still have to be fast. I can not stop users doing that kind of reporting. :( I need more speed in orders of magnitude. Will more disks / more memory do that trick? Money is of course a limiting factor but it doesn't have to be real cheap. Ulrich

Re: [PERFORM] Need for speed

postgresql.conf below. Ulrich #--- # RESOURCE USAGE (except WAL) #--- # - Memory - shared_buffers = 2 # min 16, at least max_connections*2

[PERFORM] Need for speed

in some orders of magnitude. I already thought of a box with the whole database on a ram disc. So really any idea is welcome. Ulrich -- Ulrich Wisser / System Developer RELEVANT TRAFFIC SWEDEN AB, Riddarg 17A, SE-114 57 Sthlm, Sweden Direct (+46)86789755 || Cell (+46)704467893 || Fax (+46

Re: [PERFORM] Query tuning help

and em.entrydate = '2005-5-9 00:00'::date and ( recordtext like '%RED%' or recordtext like '%CORVETTE%' ) order by em.entrydate That should give you all rows containing one of the words. Does it work? Is is faster? Is it fast enough? Ulrich ---(end of broadcast

[PERFORM] insert

Hi, is there anything I can doo to speed up inserts? One of my tables gets about 100 new rows every five minutes. And somehow the inserts tend to take more and more time. Any suggestions welcome. TIA Ulrich ---(end of broadcast)--- TIP 9