From: sathiya psql <sathiya.psql@gmail.com>
To: Bill Moran <wmoran@collaborativefusion.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: postgresql is slow with larger table even it is in RAM
Date: Tue, 25 Mar 2008 18:57:12 +0530
Message-ID: <f966c2ee0803250627gdd5f1eai61b0bbb199320fd3@mail.gmail.com> (raw)
In-Reply-To: <20080325091046.b5d50a35.wmoran@collaborativefusion.com>
References: <f966c2ee0803250135h57ba1d5bs41f77616ae7186dc@mail.gmail.com>
<20080325091046.b5d50a35.wmoran@collaborativefusion.com>
>
> Yes. It takes your hardware about 3 seconds to read through 700M of ram.
>
>
> Keep in mind that you're not just reading RAM. You're pushing system
> requests through the VFS layer of your operating system, which is treating
> the RAM like a disk (with cylinder groups and inodes and blocks, etc) so
> you have all that processing overhead as well. What filesystem did you
> format the RAM disk with?
>
tmpfs
>
> Why are you doing this? If you have enough RAM to store the table, why
> not just allocate it to shared buffers?
just allocating will make read from hdd to RAM at first time, to eliminate
that
>
>
are you saying it will take 3 seconds surely if i have 50 lakh record
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To: pgsql-performance@postgresql.org
Cc: sathiya.psql@gmail.com, wmoran@collaborativefusion.com
Subject: Re: postgresql is slow with larger table even it is in RAM
In-Reply-To: <f966c2ee0803250627gdd5f1eai61b0bbb199320fd3@mail.gmail.com>
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