On Sun, Mar 15, 2015 at 8:04 PM, Rui DeSousa <rui@crazybean.net> wrote: > Would a parameter to auto terminate long running transactions be a better solution? Terminating the long running transaction would allow for the normal vacuuming process to cleanup the deleted records thus avoiding database bloat without introducing new semantics to Postgres's MVCC. I would also recommend that the default be disabled.
An advantage of Kevin's approach is that you don't have to abort *all* long-running transactions, only those that touch data which has been modified since then. If your system is read-mostly, that could dramatically reduce the number of aborts.
Indeed. The suggestion of auto-terminating long running transactions misses the point, ISTM. Most of the use cases I can see for this involve vacuuming tables that the long running transaction will have no interest in at all (which is why I suggested being able to set it on a per table basis). I certainly don't want to be terminating my long running report transaction so that my queue table which is only ever touched by very short-lived transactions can be reasonably vacuumed. But that's what we have to do now.
