Re: [PERFORM] Test...

2003-09-29 Thread Tom Lane
David Griffiths <[EMAIL PROTECTED]> writes: > Is there a size limit to an email IIRC, the standard policy on the pgsql lists is that messages over 40K or so will be delayed for moderator approval. However, you should have gotten immediate replies from the majordomo 'bot telling you so. If you go

[PERFORM] Test...

2003-09-29 Thread David Griffiths
I've posted several emails, and have yet to see one show up (this one might not either).   Is there a size limit to an email (it had a big analyze, and schema information)?? David

Re: [PERFORM] advice on raid controller

2003-09-29 Thread Bruce Momjian
\Palle Girgensohn wrote: > Come to think of it, I guess a battery-backed cache will make fsync as fast > as no fsync, right? So, the q was kinda stoopid... :-/ With fsync off, the data might never get to the battery-backed RAM. :-( -- Bruce Momjian| http://candle.pha

Re: [PERFORM] advice on raid controller

2003-09-29 Thread Matt Clark
Not in general. Besides, with a write-back cache an fsync() is very nearly 'free', as the controller will report the write as completed as soon as it's written to cache. I keep meaning to benchmark the difference, but I only have the facility on a production box, so caution gets the better of me

Re: [PERFORM] advice on raid controller

2003-09-29 Thread Palle Girgensohn
Come to think of it, I guess a battery-backed cache will make fsync as fast as no fsync, right? So, the q was kinda stoopid... :-/ /Palle --On måndag, september 29, 2003 23.31.54 +0200 Palle Girgensohn <[EMAIL PROTECTED]> wrote: Stupid question, perhaps, but would a battery-backed cache make i

Re: [PERFORM] advice on raid controller

2003-09-29 Thread Palle Girgensohn
Stupid question, perhaps, but would a battery-backed cache make it safe to set fsync=false in postgresql.conf? /Palle --On söndag, september 28, 2003 13.07.57 +0100 Matt Clark <[EMAIL PROTECTED]> wrote: As others have mentioned, you really ought to get battery-backed cache if you're doing any

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Palle Girgensohn
--On måndag, september 29, 2003 11.12.55 -0400 Christopher Browne <[EMAIL PROTECTED]> wrote: [EMAIL PROTECTED] (Palle Girgensohn) writes: Will that make a difference? From what I've seen, it does not make much difference, but I have seen queries speed up when rewritten explicit joins. I guess i

Re: [PERFORM] advice on raid controller

2003-09-29 Thread scott.marlowe
On 29 Sep 2003, Will LaShell wrote: > On Mon, 2003-09-29 at 06:48, scott.marlowe wrote: > > I've used the megaraid / LSI cards in the past and they were pretty good > > in terms of reliability, but the last one I used was the 328 model, from 4 > > years ago or so. that one had a battery backup

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Oleg Lebedev
Yes Josh, L_partkey is a part of the foreign key on the Lineitem table, and it was ok to create an index on it according to the TPC-R specs. I just created indices on the rest of the FK columns in the TPC-R database and will continue my evaluations. Thanks. Oleg -Original Message- From:

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Josh Berkus
Oleg, > I just checked the restrictions on the TPC-R and TPC-H schemas and it > seems that all indexes are allowed in TPC-R and only those that index > parts of primary or foreign keys are allowed in TPC-H. That would be appropriate for this case though, yes? That column is part of a foriegn k

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Andrew Sullivan
On Mon, Sep 29, 2003 at 05:43:26PM -, [EMAIL PROTECTED] wrote: > > Anyone have a rough idea of the costs involved? I did a back-of-an-envelope calculation one day and stopped when I got to $10,000. A -- Andrew Sullivan 204-4141 Yonge Street Afilias Canada

Re: [PERFORM] advice on raid controller

2003-09-29 Thread Will LaShell
On Mon, 2003-09-29 at 06:48, scott.marlowe wrote: > I've used the megaraid / LSI cards in the past and they were pretty good > in terms of reliability, but the last one I used was the 328 model, from 4 > years ago or so. that one had a battery backup option for the cache, and > could go to 128

Re: [PERFORM] Performance: BigInt vs Decimal(19,0)

2003-09-29 Thread Josh Berkus
Franco, > Wouldn't it be the most portable solution to work with a domain? > CREATE DOMAIN BIG_NUMBER AS BIGINT; > > If I use BIG_NUMBER everywhere I need it in my database, porting it to > other database products should be easy... any SQL 92 compliant dbms > should support domains. This is a goo

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread greg
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 > I'm pretty certain that there are no TPC-certified test results for > Postgres, because to date no organization has cared to spend the money > needed to perform a certifiable test. Anyone have a rough idea of the costs involved? - -- Greg Sabino

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Oleg Lebedev
Oops, my previous message got cut off. Here is the end of it: I just checked the restrictions on the TPC-R and TPC-H schemas and it seems that all indexes are allowed in TPC-R and only those that index parts of primary or foreign keys are allowed in TPC-H. Thanks. Oleg -Original Message

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Tom Lane
Shridhar Daithankar <[EMAIL PROTECTED]> writes: > Also if you have fast disk drives, you can reduce random page cost to 2 or 1.5. Note however that most of the people who have found smaller random_page_cost to be helpful are in situations where most of their data fits in RAM. Reducing the cost to

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Oleg Lebedev
It took 10 hours to compute the query without the index on lineitem.l_partkey. Once I created the index on lineitem.l_partkey, it took only 32 secs to run the same query. After VACUUM ANALYZE it took 72 secs to run the query. All the subsequent runs took under 3 seconds! That's quite amazing!

Re: [PERFORM] Performance: BigInt vs Decimal(19,0)

2003-09-29 Thread Andrew Rawnsley
On Saturday, September 27, 2003, at 10:39 PM, Yusuf W. wrote: Now, I've got to convince my project's software architech, that a bigint would be better than a decimal. Does anyone know where I could get some documentation on how the int and decimal are implemented so I could prove to him that ints

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Gaetano Mendola
Palle Girgensohn wrote: Will that make a difference? From what I've seen, it does not make much difference, but I have seen queries speed up when rewritten explicit joins. I guess it depends on other things, but is it really so that the explicit joins are bad somehow? Do you have any pointers to

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Gaetano Mendola
Palle Girgensohn wrote: uu=# explain analyze uu-# select lower(substr(p.last_name,1,1)) as letter, count(*) uu-# FROM course c join group_data gd on (c.active_group_id = gd.this_group_id) uu-# join person p on (gd.item_text = p.userid) uu-# join dyn_field_person dfp on (dfp.extern_it

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Christopher Browne
[EMAIL PROTECTED] (Palle Girgensohn) writes: > Will that make a difference? From what I've seen, it does not make > much difference, but I have seen queries speed up when rewritten > explicit joins. I guess it depends on other things, but is it really > so that the explicit joins are bad somehow? D

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Tom Lane
Mary Edie Meredith <[EMAIL PROTECTED]> writes: > Valid TPC-R benchmark results are on the TPC web site: > http://www.tpc.org/tpcr/default.asp > I do not see one for PostgreSQL. I'm pretty certain that there are no TPC-certified test results for Postgres, because to date no organization has cared

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Mary Edie Meredith
On Mon, 2003-09-29 at 07:35, Oleg Lebedev wrote: > I left my TPC-R query #17 working over the weekend and it took 3988 mins > ~ 10 hours to complete. And this is considering that I am using a TPC-R > database created with a scale factor of 1, which corresponds to ~1 GB of > data. I am running RedHa

Re: [PERFORM] Plan-Reading

2003-09-29 Thread greg
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 > Where can I find a plan-readinf tutorial? This covers explain plans in depth: http://www.gtsm.com/oscon2003/explain.html - -- Greg Sabino Mullane [EMAIL PROTECTED] PGP Key: 0x14964AC8 200309291123 -BEGIN PGP SIGNATURE- Comment: http://

Re: [PERFORM] Performance: BigInt vs Decimal(19,0)

2003-09-29 Thread Franco Bruno Borghesi
Wouldn't it be the most portable solution to work with a domain? CREATE DOMAIN BIG_NUMBER AS BIGINT; If I use BIG_NUMBER everywhere I need it in my database, porting it to other database products should be easy... any SQL 92 compliant dbms should support domains. On Sun, 2003-09-28 at 00:06,

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Shridhar Daithankar
Oleg Lebedev wrote: effective_cache_size = 32000 # typically 8KB each That is 256MB. You can raise it to 350+MB if nothing else is running on the box. Also if you have fast disk drives, you can reduce random page cost to 2 or 1.5. I don't know how much this will make any difference to benchmark r

Re: [PERFORM] TPC-R benchmarks

2003-09-29 Thread Oleg Lebedev
I left my TPC-R query #17 working over the weekend and it took 3988 mins ~ 10 hours to complete. And this is considering that I am using a TPC-R database created with a scale factor of 1, which corresponds to ~1 GB of data. I am running RedHat 8.0 on a dual 1 GHz processor, 512 MB RAM. Here is an

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Gaetano Mendola
Palle Girgensohn wrote: Will that make a difference? From what I've seen, it does not make much difference, but I have seen queries speed up when rewritten explicit joins. I guess it depends on other things, but is it really so that the explicit joins are bad somehow? Do you have any pointers to

Re: [PERFORM] advice on raid controller

2003-09-29 Thread scott.marlowe
I've used the megaraid / LSI cards in the past and they were pretty good in terms of reliability, but the last one I used was the 328 model, from 4 years ago or so. that one had a battery backup option for the cache, and could go to 128 Meg. We tested it with 4/16 and 128 meg ram, and it was

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Palle Girgensohn
--On måndag, september 29, 2003 15.32.31 +0200 Gaetano Mendola <[EMAIL PROTECTED]> wrote: Are not absolutelly bad but sometimes that path that you choose is not the optimal, in postgres 7.4 use the explicit join will be less limitative for the planner. Regards Gaetano Mendola Ah, OK. True! In thi

Re: [PERFORM] avoiding seqscan?

2003-09-29 Thread Palle Girgensohn
Will that make a difference? From what I've seen, it does not make much difference, but I have seen queries speed up when rewritten explicit joins. I guess it depends on other things, but is it really so that the explicit joins are bad somehow? Do you have any pointers to documentation about it,