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From: Dave Stibrany <[email protected]>
To: Sumeet Shukla <[email protected]>
Cc: [email protected]
Subject: Re: Dataset is fetched from cache but still takes same time to fetch records as first run
Date: Thu, 22 Jun 2017 20:54:41 -0400
Message-ID: <CAK17Jmm6WBXy-4-_H21PAopoU5o=FyoLwjBkPeJCNHCU59z-Qw@mail.gmail.com> (raw)
In-Reply-To: <CABUL137pc8pfW+KLm=7ucXpSDi_eG2qWiFMdR-3-UMEkZ=QUqA@mail.gmail.com>
References: <CABUL137pc8pfW+KLm=7ucXpSDi_eG2qWiFMdR-3-UMEkZ=QUqA@mail.gmail.com>
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The numbers you posted look exactly as I would expect. The first read hits
disk and takes 108ms, the second read hits the cache and takes 27ms.

On Thu, Jun 22, 2017 at 8:40 PM, Sumeet Shukla <[email protected]>
wrote:

> Both the first run and subsequent run takes same amount of time.
>
> *First Run:*
>
> "Seq Scan on d_payer (cost=0.00..8610.40 rows=121788 width=133) (actual
> time=8.760..98.582 rows=121788 loops=1)"
> " *Buffers: shared read=2521*"
> "Planning time: 16.820 ms"
> "Execution time: 108.626 ms"
>
>
> *Second Run:*
>
> "Seq Scan on d_payer (cost=0.00..8610.40 rows=121788 width=133) (actual
> time=0.010..18.456 rows=121788 loops=1)"
> " *Buffers: shared hit=2521*"
> "Planning time: 0.083 ms"
> "Execution time: 27.288 ms"
>
>
> Can anyone please help me understand and fix this.
>
>
> Thanks & Regards,
> Sumeet Shukla
>
>

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