Execute vacuum online

Question

I'm new with PostgreSQL, so I hope that this is question is ok.

If I want to execute a vacuum operation (manual or auto).

Is that operation can make problems to end-users or anything with queries or other DML commands?

I'm using version 9.6

PostgreSQL 9.6.6 on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4, 64-bit — user2671057, May 02 '18 at 07:08

score 0 · Answer 1 · edited May 02 '18 at 07:05

0

Vacuum has a cost in terms of IO on database, but, as in documentation:

Plain VACUUM (without FULL) simply reclaims space and makes it available for re-use. This form of the command can operate in parallel with normal reading and writing of the table, as an exclusive lock is not obtained.

If you need FULL vacuum, to release space to OS:

Selects "full" vacuum, which can reclaim more space, but takes much longer and exclusively locks the table.

You can dig deep here: https://www.postgresql.org/docs/current/static/sql-vacuum.html

edited May 02 '18 at 07:05

answered May 02 '18 at 06:56

user_0

3,173
20
33

Thanks! so if it's a vacuum without full there is no expected problems, right? – user2671057 May 02 '18 at 07:09
Correct. Just more load on the system, but no locks. – user_0 May 02 '18 at 07:28
No locks, but maybe it can cause performance issues, isn't it? – user2671057 May 02 '18 at 07:56
Exact. If you run it often, impact is minimal. Just consider your load. – user_0 May 02 '18 at 08:49

Execute vacuum online

1 Answers1