Date: Sun, 22 Mar 2020 20:29:04 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: Arya F <arya6000@gmail.com>
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: Partitions to improve write/update speed for tables with indexes?
Message-ID: <20200323012904.GG2563@telsasoft.com>
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On Sun, Mar 22, 2020 at 09:22:50PM -0400, Arya F wrote:
> I have noticed that my write/update performance starts to dramatically
> reduce after about 10 million rows on my hardware. The reason for the
> slowdown is the index updates on every write/update.

It's commonly true that the indexes need to fit entirely in shared_buffers for
good write performance.  I gave some suggestions here:
https://www.postgresql.org/message-id/20200223101209.GU31889%40telsasoft.com

> The solution would be partitioning? One of my tables will have more
> than 1 billion rows of data, so I would have to create about 100
> partitions for that table. Is the a practical limit to the amount of
> partitions I can have with Postgresql 12?

The recommendation since pg12 is to use at most a "few thousand" partitions, so
for the moment you'd be well within the recommendation.
https://www.postgresql.org/docs/12/ddl-partitioning.html

-- 
Justin