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waiting for harddisk
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* waiting for harddisk
@ 2008-03-24 13:05 petchimuthu lingam <spmlingam@gmail.com>
  2008-03-24 13:20 ` Re: waiting for harddisk PFC <lists@peufeu.com>
  2008-03-25 01:13 ` Re: waiting for harddisk Scott Marlowe <scott.marlowe@gmail.com>
  0 siblings, 2 replies; 3+ messages in thread

From: petchimuthu lingam @ 2008-03-24 13:05 UTC (permalink / raw)
  To: pgsql-performance

i am using postgresql 8.1.8,

Following configurations:
           shared_buffers = 5000
            work_mem = 65536
            maintenance_work_mem = 65536
            effective_cache_size = 16000
            random_page_cost = 0.1

The cpu is waiting percentage goes upto 50%, and query result comes later,

i am using normal select query ( select * from table_name ).

table has more then 6 million records.



-- 
With Best Regards,
Petchimuthulingam S

^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: waiting for harddisk
  2008-03-24 13:05 waiting for harddisk petchimuthu lingam <spmlingam@gmail.com>
@ 2008-03-24 13:20 ` PFC <lists@peufeu.com>
  1 sibling, 0 replies; 3+ messages in thread

From: PFC @ 2008-03-24 13:20 UTC (permalink / raw)
  To: petchimuthu lingam <spmlingam@gmail.com>; pgsql-performance

> i am using postgresql 8.1.8,
>
> Following configurations:
>            shared_buffers = 5000
>             work_mem = 65536
>             maintenance_work_mem = 65536
>             effective_cache_size = 16000
>             random_page_cost = 0.1
>
> The cpu is waiting percentage goes upto 50%, and query result comes  
> later,
>
> i am using normal select query ( select * from table_name ).
>
> table has more then 6 million records.



	When you mean SELECT *, are you selecting the WHOLE 6 million records ?  
Without WHERE ? Or just a few rows ?
	Please post EXPLAIN ANALYZE of your query.



^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: waiting for harddisk
  2008-03-24 13:05 waiting for harddisk petchimuthu lingam <spmlingam@gmail.com>
@ 2008-03-25 01:13 ` Scott Marlowe <scott.marlowe@gmail.com>
  1 sibling, 0 replies; 3+ messages in thread

From: Scott Marlowe @ 2008-03-25 01:13 UTC (permalink / raw)
  To: petchimuthu lingam <spmlingam@gmail.com>; +Cc: pgsql-performance

On Mon, Mar 24, 2008 at 7:05 AM, petchimuthu lingam <spmlingam@gmail.com> wrote:
> i am using postgresql 8.1.8,
>
> Following configurations:
>            shared_buffers = 5000
>             work_mem = 65536
>             maintenance_work_mem = 65536
>             effective_cache_size = 16000
>              random_page_cost = 0.1

That number, 0.1 is not logical.  anything below 1.0 is generally a
bad idea, and means that you've got some other setting wrong.

> The cpu is waiting percentage goes upto 50%, and query result comes later,
>
> i am using normal select query ( select * from table_name ).
>
> table has more then 6 million records.

You need faster disks if you want sequential scans to go faster.  Look
into a decent RAID controller (Areca, Escalade (forgot what they're
called now) or LSI) with battery backed cache.  Run RAID-10 on it with
as many drives as you can afford to throw at the problem.



^ permalink  raw  reply  [nested|flat] 3+ messages in thread


end of thread, other threads:[~2008-03-25 01:13 UTC | newest]

Thread overview: 3+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2008-03-24 13:05 waiting for harddisk petchimuthu lingam <spmlingam@gmail.com>
2008-03-24 13:20 ` PFC <lists@peufeu.com>
2008-03-25 01:13 ` Scott Marlowe <scott.marlowe@gmail.com>

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