pg_compacttable takes way too much time compacting a table

[ramili4]

Hi there! First off, a big shoutout to the developers of pg_compacttable! It's a really useful tool. I've noticed it can be a bit slow on larger tables. I was wondering if there are any parameters or configuration options that can be tweaked to speed it up somehow? Are there any best practices for optimizing its performance when dealing with substantial datasets so it takes less time to compact tables?

[Melkij]

--delay-ratio=0 mostly (disable sleep between iterations)
--initial-reindex can be useful: the indexes will be rebuilt first, so subsequent updates will create less IO when updating the indexes.

But in general pgcompacttable is quite slow (which is not bad as it does not create a huge system load). You might also find pg_repack useful.