Re: rebuild big tables with pgrepack

On Fri, Nov 14, 2025 at 2:14 PM ek ek <livadidrive(at)gmail(dot)com> wrote:

> Hello everyone,
> I’m going to rebuild a 900GB table using pg_repack. I’m hesitant to do
> such a large operation in one go.
> Is there an ideal or recommended way to repack very large tables?
>

Everything in database maintenance is circumstantial.

The basics that I'd do are:
* Verify that you have enough free disk space for both the new table, the
new indices and also the WALs generated.
* Do it during a low-activity window.
* Don't run a database backup at the same time.
* First execute with --dry-run.
* Consider the --no-order option. That'll speed things up.
* And --no-analyze, though you'll have to manually ANALYZE immediately
afterwards.
* (I'd probably disable autoanalyze on that table before the repack and
then enable it after the manual ANALYZE.)
* The --jobs option speeds up index rebuilds.
* Run it from cron, and redirect both stdout and stderr to the same log
file.

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