Re: Request: pg_cancel_backend variant that handles 'idle in transaction' sessions

2015-11-05 19:56 GMT+01:00 Joe Conway <mail(at)joeconway(dot)com>:

> On 11/05/2015 10:48 AM, Pavel Stehule wrote:
> > S
> > t C
> > a<-------------<transaction>--------------->E
> > r A B A B A n
> > t <idle> <stmt> <idle> <stmt> <idle> d
> > |--------======--------======---------------|
> >
> > Currently we can set timeout and cancel for period B (<stmt>). I can
> see
> > based on this discussion that there are legitimate use cases for
> wanting
> > timeout and cancel for any of the periods A, B, or C.
> >
> > I guess the question then becomes how we provide that coverage. I
> think
> > for coverage of timeout you need three individual timeout settings.
> > However for cancel, it would seem that pg_cancel_transaction would
> cover
> > all three cases.
> >
> >
> > It can be difficult to set it properly, because you don't know how much
> > statements (cycles of A.B) will be in transaction. Respective for
> > setting C, I have to know the number of A,B and it isn't possible
> everytime.
>
> But you might have a limit you want to enforce regardless of the size or
> quantity of A & B periods. That's why it needs to be a separate timeout
> IMHO. Let's say I never want a transaction to be around more than 60
> minutes no matter what. But I also don't want idle in transaction to
> ever exceed 30 seconds, and I don't expect individual statements to
> exceed 10 minutes.
>

I am not sure due my wrong English if we are in agreement or not, I am
sorry :/ - Any mentioned timeouts are useful and covers little bit
different issues - and we need all.

Regards

Pavel

>
> Joe
>
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