[PERFORM] pgbench to the MAXINT

2011-01-07 Thread Greg Smith
At one point I was working on a patch to pgbench to have it adopt 64-bit math internally even when running on 32 bit platforms, which are currently limited to a dataabase scale of ~4000 before the whole process crashes and burns. But since the range was still plenty high on a 64-bit system, I

Re: [PERFORM] Wrong docs on wal_buffers?

2011-01-07 Thread Greg Smith
Samuel Gendler wrote: I was trying to make the point that, in an attempt to make things very easy for novice users, we are actually making them quite a bit more complex for novice users who want to do anything besides start the server. People who can't start the server often abandon PostgreSQL

Re: [PERFORM] Wrong docs on wal_buffers?

2011-01-07 Thread Samuel Gendler
On Fri, Jan 7, 2011 at 7:07 AM, Tom Lane wrote: > Samuel Gendler writes: > > Does it not seem that this insistence on shipping a default config that > > works out of the box on every system incurs a dramatic penalty when it > comes > > to getting a useful postgres config for a production system?

Re: [PERFORM] Wrong docs on wal_buffers?

2011-01-07 Thread Tom Lane
Samuel Gendler writes: > Does it not seem that this insistence on shipping a default config that > works out of the box on every system incurs a dramatic penalty when it comes > to getting a useful postgres config for a production system? > I'm sure this argument has probably been done to death o

Re: [PERFORM] Wrong docs on wal_buffers?

2011-01-07 Thread Samuel Gendler
On Thu, Jan 6, 2011 at 8:37 PM, Greg Smith wrote: > Josh Berkus wrote: > >> We talked about bumping it to 512kB or 1MB for 9.1. Did that get in? >> Do I need to write that patch? >> >> > > If it defaulted to 3% of shared_buffers, min 64K & max 16MB for the auto > setting, it would for the most p

Re: [PERFORM] plan question - query with order by and limit not choosing index depends on size of limit, table

2011-01-07 Thread pasman pasmański
Try order by created_at+0 On 1/6/11, Mike Broers wrote: > Thanks for the assistance. > > Here is an explain analyze of the query with the problem limit: > > production=# explain analyze select * from landing_page.messages where > ((messages.topic = E'x') AND (messages.processed = 'f')) ORDER BY

Re: [PERFORM] Wrong docs on checkpoint_segments?

2011-01-07 Thread Andres Freund
On Friday, January 07, 2011 02:45:02 PM Florian Weimer wrote: > * Andres Freund: > > On Friday, January 07, 2011 01:45:25 PM Florian Weimer wrote: > >> On 9.0, this configuration > >> > >> checkpoint_segments = 512 # in logfile segments, min 1, 16MB each > >> > >> results in 1034 segments, so

Re: [PERFORM] Wrong docs on checkpoint_segments?

2011-01-07 Thread Florian Weimer
* Andres Freund: > On Friday, January 07, 2011 01:45:25 PM Florian Weimer wrote: >> On 9.0, this configuration >> >> checkpoint_segments = 512 # in logfile segments, min 1, 16MB each >> >> results in 1034 segments, so the effective logfile segment size is 32 MB. > Um. Is it possible that you

Re: [PERFORM] Wrong docs on checkpoint_segments?

2011-01-07 Thread Andres Freund
On Friday, January 07, 2011 01:45:25 PM Florian Weimer wrote: > On 9.0, this configuration > > checkpoint_segments = 512 # in logfile segments, min 1, 16MB each > > results in 1034 segments, so the effective logfile segment size is 32 MB. Um. Is it possible that you redefined XLOG_SEG_SIZE or

[PERFORM] Wrong docs on checkpoint_segments?

2011-01-07 Thread Florian Weimer
On 9.0, this configuration checkpoint_segments = 512 # in logfile segments, min 1, 16MB each results in 1034 segments, so the effective logfile segment size is 32 MB. The documentation says this: Maximum number of log file segments between automatic WAL checkpoints (each segment is

Re: [PERFORM] "SELECT .. WHERE NOT IN" query running for hours

2011-01-07 Thread Γιωργος Βαλκανας
Fair enough! I also turned seqscan off, so the new plan (for the NOT EXISTS) is: Merge Anti Join (cost=0.00..212686.89 rows=1 width=313) (actual time=0.426..14921.344 rows=63836 loops=1) Merge Cond: ((d2.hwdocid)::text = (d.hwdocid)::text) -> Index Scan using hwdocid2_uniq on "Doc2" d2 (cost=0.

Re: [PERFORM] How to turn autovacuum prevent wrap around run faster?

2011-01-07 Thread marc47marc47
Hi All: The autovacuum (prevent wraparound) still run more than 36 hours, I can not drop the partition table after adjust the autovacuum parameters. If a table is running autovacuum (prevent wraparound), can I purge this table? If not, what else I can do for clean this partition table? If the t

Re: [PERFORM] Major performance problem after upgrade from 8.3 to 8.4

2011-01-07 Thread Marc Antonio
Hi, I had a similar problem with many left join, reading about planning optimization i tried to edit postgresql.conf and uncommented the line join_collapse_limit = 8 and set it to 1, disables collapsing of explicit . My query its taking 2000s in 8.4 and the same query 2ms in 8.3. Now its working

Re: [PERFORM] adding foreign key constraint locks up table

2011-01-07 Thread kakarukeys
On Dec 28 2010, 9:55 pm, kakarukeys wrote: > On Dec 28, 9:37 pm, singh.gurj...@gmail.com (Gurjeet Singh) wrote: > > > > > On Tue, Dec 28, 2010 at 2:08 AM, kakarukeys wrote: > > > I have a table "aaa" which is not very big. It has less than 10'000 > > > rows. However read operations on this table

Re: [PERFORM] How to turn autovacuum prevent wrap around run faster?

2011-01-07 Thread marc.hsiao
Hi All: The autovacuum (prevent wraparound) still run more than 36 hours, I can not drop the partition table after adjust the autovacuum parameters. If a table is running autovacuum (prevent wraparound), can I purge this table? If not, what else I can do for clean this partition table? If the t