Re: [PERFORM] Optimizer seems to be way off, why?

2005-07-20 Thread John A Meinel
Dirk Lutzebäck wrote: > Richard Huxton wrote: > >> Dirk Lutzebäck wrote: >> >>> Hi, >>> >>> I do not under stand the following explain output (pgsql 8.0.3): >>> >>> explain analyze >>> select b.e from b, d >>> where b.r=516081780 and b.c=513652057 and b.e=d.e; >>> >>>

Re: [PERFORM] performance decrease after reboot

2005-07-20 Thread John Mendenhall
On Tue, 19 Jul 2005, John Mendenhall wrote: > I tuned a query last week to obtain acceptable performance. > Here is my recorded explain analyze results: > > LOG: duration: 826.505 ms statement: explain analyze > [cut for brevity] > > I rebooted the database machine later that night. > Now, when

Re: [PERFORM] Optimizer seems to be way off, why?

2005-07-20 Thread Dirk Lutzebäck
Richard Huxton wrote: Dirk Lutzebäck wrote: Hi, I do not under stand the following explain output (pgsql 8.0.3): explain analyze select b.e from b, d where b.r=516081780 and b.c=513652057 and b.e=d.e; QUERY PLAN

Re: [PERFORM] Optimizer seems to be way off, why?

2005-07-20 Thread Richard Huxton
Dirk Lutzebäck wrote: Hi, I do not under stand the following explain output (pgsql 8.0.3): explain analyze select b.e from b, d where b.r=516081780 and b.c=513652057 and b.e=d.e; QUERY PLAN

Re: [PERFORM] Impact of checkpoint_segments under continual load conditions

2005-07-20 Thread Christopher Petrilli
On 7/19/05, Christopher Petrilli <[EMAIL PROTECTED]> wrote: > It looks like the CVS HEAD is definately "better," but not by a huge > amount. The only difference is I wasn't run autovacuum in the > background (default settings), but I don't think this explains it. > Here's a graph of the difference

Re: [PERFORM] Impact of checkpoint_segments under continual load conditions

2005-07-20 Thread Christopher Petrilli
On 7/19/05, Christopher Petrilli <[EMAIL PROTECTED]> wrote: > On 7/19/05, Tom Lane <[EMAIL PROTECTED]> wrote: > > Christopher Petrilli <[EMAIL PROTECTED]> writes: > > > On 7/19/05, Tom Lane <[EMAIL PROTECTED]> wrote: > > >> How *exactly* are you invoking psql? > > > > > It is a subprocess of a Pyth

[PERFORM] Optimizer seems to be way off, why?

2005-07-20 Thread Dirk Lutzebäck
Hi, I do not under stand the following explain output (pgsql 8.0.3): explain analyze select b.e from b, d where b.r=516081780 and b.c=513652057 and b.e=d.e; QUERY PLAN ---