Re: [GENERAL] Modified rows are not marked as dead and as such vacuum is unable to clean them up

Hi Tom,

just cleaned house in my mailbox and found this email that got buried. You
were spot on with the prepared transactions, we had some hung Hibernate
threads that were acting up.

Sorry for resurrecting this ages old thread, but wanted to say a big fat
*THANKS*!

Cheers,
Tamas Kalman.

On Thu, Jul 6, 2017 at 11:25 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> =?UTF-8?B?VGFtw6FzIEFuZHLDoXMgS8OhbG3DoW4=?= <hello(at)tamaskalman(dot)com>
> writes:
> > we have a PostgreSQL 9.3.4 database with multiple large tables, that keep
> > growing.
> > Looking at the pg_stat of the front runner table that is currently
> about 1
> > Gb big, it seems, that stale row data is not marked as dead after
> updates,
>
> Have you checked for uncommitted prepared transactions?
> If "select * from pg_prepared_xacts" finds anything, that's
> probably your problem.
>
> regards, tom lane
>