Subject: Re: sizing / capacity planning tipps related to expected request or
 transactions per second
To: Dirk Krautschick <Dirk.Krautschick@trivadis.com>
Cc: "pgsql-performance@lists.postgresql.org"
 <pgsql-performance@lists.postgresql.org>
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From: MichaelDBA <MichaelDBA@sqlexec.com>
Message-ID: <bee06a6c-f409-c5d2-daa1-5340ed3ee2f9@sqlexec.com>
Date: Mon, 24 Aug 2020 12:49:21 -0400
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Hi Dirk,

There are a bunch of other things to consider besides just TPS and size 
of database.  Since PG is process-bound, I would consider connection 
activity: How many active connections at any one time?  This greatly 
affects your CPUs.  SQL workload is another big factor: a lot of complex 
queries may use up or want to use up large amounts of work_mem, which 
greatly affects your memory capacity.

Bunch of other stuff, but these are my top 2.


Regards,
Michael Vitale

Dirk Krautschick wrote on 8/24/2020 12:39 PM:
> Hi,
>
> are there any nice rules of thumb about capacity planning in relation the expected
> amount of transactions or request per second?
>
> For example, if I have around 100 000 transactions per second on a 5 TB database.
> With what amount of Memory and CPUs/Cores and which settings would you basically
> Start to evaluate the performance.
>
> Or are there any other recommendations or experiences here?
>
> Thanks and best regards
>
> Dirk