Is it ok to run vacuum full verbose command for live database for the tables which has more dead tuples?

Question

We have thousands of tables. But out of those tables, around 20 to 40 tables are always busy due to that those tables are bloating.

In order to avoid this we are running a shell script which performs vacuum full on the tables which has more than ten thousand dead tuples. While running this we are stopping all application processors and running vacuum full on the tables which has more dead tuples.

Is it ok to run vacuum full verbose command for live database for the tables which has more dead tuples(greater than)? Does it cause any adverse effect?

We are using 9.2 postgresql version.

Please clarify me. Thanks in advance.

Answer 1

'Adverse' depends on your opinion but when running on a live application that relies on access to these tables then yes.

Running full vacuum will lock these tables and re-write them reclaiming disk space to the operating system, vacuum will not reduce the size of the table but will free up used space for use with it.

https://www.postgresql.org/docs/9.2/static/sql-vacuum.html