PostgreSQL server

I've never noticed the difference in PG zabbix databases.
Indeed, schema for zabbix 1.8 for PG use such syntax for each table:

CREATE TABLE slideshows (
        slideshowid             bigint          DEFAULT '0'     NOT NULL,
        name            varchar(255)            DEFAULT ''      NOT NULL,
        delay           integer         DEFAULT '0'     NOT NULL,
        PRIMARY KEY (slideshowid)
) with OIDS;

2.0 already does not have it.

It could be fixed with upgrade patches, but ... the time required is a serious aspect.
Not sure how to fix it in better way. Maybe just print some message in zabbix_server.log on daemon start with suggestion to perform the change manually in a separate maintenance window ...

In a ZBXNEXT-3550 you described other index changes (which reduced used space too), so is that correct that 60% mentioned in current issue is caused by OIDs drop only ?

Issue moved to ZBX project, as it's closer to a bug.

The graph on that blog post is for the OID drop only. I'm expecting another 40% disk usage drop by implementing the changes from ZBXNEXT-3550. After that, I have some more changes ( not yet written about ) that can give further reduction on historical data ( early tests showed that a 3GiB table could get shrunk down to 700MiB, ) but the performance suffered.

So yes, OID dropping alone caused a 60% reduction on one of our DB machines.

I expect that is because those tables were slightly bloated, and a normal expectation would be 15-20% reduction due to OID.

I reduced my database size by almost 50% after removing the oid from my database.

Since the issue only affects versions ≤1.8 upgrading to a newer versions and 1.8 is out of support for quite some time, I'm closing this issue as Unsupported version.