Re: Large tables, ORDER BY and sequence/index scans

From: John R Pierce <pierce(at)hogranch(dot)com>
To: Milan Zamazal <pdm(at)brailcom(dot)org>
Cc: Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>, pgsql-general(at)postgresql(dot)org
Subject: Re: Large tables, ORDER BY and sequence/index scans
Date: 2010-01-05 17:16:22
Message-ID: 4B4373E6.9080208@hogranch.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Milan Zamazal wrote:
> PS> and value efective_cache_size ???
>
> effective_cache_size = 128MB
>

thats rather small unless your systme is very memory constrained.
assuming postgres is the primary disk IO consumer on this ysstem, take a
look at the 'cached' value on TOP or whatever after its been running,
thats a good first order estimate of effective_cache_size.... this is
often half or more of your physical memory.

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Merlin Moncure 2010-01-05 17:49:49 pl/perl not rethrowing pl/pgsql exceptions
Previous Message frank joerdens 2010-01-05 17:02:53 reason for default PGSTAT_ACTIVITY_SIZE