Subject: Re: Bypassing shared_buffers

From: Vladimir Churyukin <[email-masked]>
Date: Wed, 14 Jun 2023 18:14:06 -0700

To be clear, I'm talking about bypassing shared buffers for reading data /
indexes only, not about disabling it completely (which I guess is
impossible anyway).

-Vladimir Churyukin

On Wed, Jun 14, 2023 at 5:57 PM Vladimir Churyukin <[email-masked]>
wrote:

> Hello,
>
> There is often a need to test particular queries executed in the
> worst-case scenario, i.e. right after a server restart or with no or
> minimal amount of data in shared buffers. In Postgres it's currently hard
> to achieve (other than to restart the server completely to run a single
> query, which is not practical). Is there a simple way to introduce a GUC
> variable that makes queries bypass shared_buffers and always read from
> storage? It would make testing like that orders of magnitude simpler. I
> mean, are there serious technical obstacles or any other objections to that
> idea in principle?
>
>  Thanks,
> -Vladimir Churyukin
>