Re: VACUUM FREEZE vs plain VACUUM

On Thursday, July 17, 2025, Ron Johnson <ronljohnsonjr(at)gmail(dot)com> wrote:

> On Thu, Jul 17, 2025 at 6:26 PM David G. Johnston <
> david(dot)g(dot)johnston(at)gmail(dot)com> wrote:
>
>> On Thursday, July 17, 2025, Ron Johnson <ronljohnsonjr(at)gmail(dot)com> wrote:
>>>
>>> Does VACUUM FREEZE do something extra or special than to defer
>>> autovacuum for an extra 50,000,000 transactions?
>>>
>>
>> It effectively resets the pseudo-counter(s) that autovacuum uses to
>> determine when next it should perform an aggressive scan. Or, put
>> differently, it does exactly what autovacuum would do when the
>> pseudo-counter(s) hit their thresholds. The act of doing that thing
>> effectively resets said counters to zero at that moment (absent concurrent
>> activity).
>>
>
> That seems to be what I said. Or am I still missing something?
>

Well, it would defer autovacuum freeze for 60,000,000 if no new rows were
inserted into your table in the subsequent 10,000,000 transactions…and
autovacuum would run (but not aggressively) if you performed a bunch of
deletes or updates…

David J.