Feedback-ID: id4a34324:Fastmail
Date: Mon, 13 Mar 2023 13:41:19 -0700
From: Andres Freund <andres@anarazel.de>
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: Transparent column encryption
Message-ID: <20230313204119.4mkepdvixcxrwpsc@awork3.anarazel.de>
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Hi,

On 2023-03-13 21:22:29 +0100, Peter Eisentraut wrote:
> On 12.03.23 01:11, Andres Freund wrote:
> > Have you done benchmarks of some simple workloads to verify this doesn't cause
> > slowdowns (when not using encryption, obviously)? printtup.c is a performance
> > sensitive portion for simple queries, particularly when they return multiple
> > columns.
> 
> The additional code isn't used when column encryption is off, so there
> shouldn't be any impact.

It adds branches, and it makes tupledescs wider. In tight spots, such as
printtup, that can hurt, even if the branches aren't ever entered.

Greetings,

Andres Freund