From: Scott Marlowe <scott.marlowe@gmail.com>
To: petchimuthu lingam <spmlingam@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: waiting for harddisk
Date: Mon, 24 Mar 2008 19:13:28 -0600
Message-ID: <dcc563d10803241813g43cab94dtb3438b6df55ec533@mail.gmail.com> (raw)
In-Reply-To: <cd233fc30803240605k2a7ae66w90487449ae07d051@mail.gmail.com>
References: <cd233fc30803240605k2a7ae66w90487449ae07d051@mail.gmail.com>
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.
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To: pgsql-performance@postgresql.org
Cc: scott.marlowe@gmail.com, spmlingam@gmail.com
Subject: Re: waiting for harddisk
In-Reply-To: <dcc563d10803241813g43cab94dtb3438b6df55ec533@mail.gmail.com>
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