Date: Tue, 23 Jul 2019 07:58:03 -0500
From: Kenneth Marshall <ktm@rice.edu>
To: Kristian Ejvind <Kristian.Ejvind@resurs.se>
Cc: "pgsql-performance@lists.postgresql.org"
 <pgsql-performance@lists.postgresql.org>
Subject: Re: zabbix on postgresql - very slow delete of events
Message-ID: <20190723125803.GD21184@aart.rice.edu>
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On Tue, Jul 23, 2019 at 08:07:55AM +0000, Kristian Ejvind wrote:
> Hi
> 
> This will be a rather lengthy post, just to give the full (I hope) picture. We're using Zabbix for monitoring and I'm having problems
> understanding why the deletion of rows in the events table is so slow.
> 
> Zabbix: 4.2 (never mind the name of the db - it is 4.2)
> new values per second: ~400
> hosts: ~600
> items: ~45000
> 

Hi Kristian,

Time series databases like Zabbix work poorly with the Housekeeper
service. We had many similar sorts of problems as our Zabbix usage
grew. Once we partitioned the big tables, turned off the Housekeeper,
and cleaned up by dropping partitions instead everything worked much,
much, much better. When we started using partitioning, we used the
old inheiritance style. Now you can use the native partitioning.

Regards,
Ken