Re: Time delayed LR (WAS Re: logical replication restrictions) - Mailing list pgsql-hackers

From Kyotaro Horiguchi
Subject Re: Time delayed LR (WAS Re: logical replication restrictions)
Date
Msg-id 20230130.131324.1149781696284954193.horikyota.ntt@gmail.com
Whole thread Raw
In response to Re: Time delayed LR (WAS Re: logical replication restrictions)  (Amit Kapila <amit.kapila16@gmail.com>)
Responses Re: Time delayed LR (WAS Re: logical replication restrictions)
List pgsql-hackers
At Mon, 30 Jan 2023 08:51:05 +0530, Amit Kapila <amit.kapila16@gmail.com> wrote in 
> On Mon, Jan 30, 2023 at 8:32 AM Kyotaro Horiguchi
> <horikyota.ntt@gmail.com> wrote:
> >
> > At Sat, 28 Jan 2023 04:28:29 +0000, "Takamichi Osumi (Fujitsu)" <osumi.takamichi@fujitsu.com> wrote in
> > > On Friday, January 27, 2023 8:00 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> > > > So, you have changed min_apply_delay from int64 to int32, but you haven't
> > > > mentioned the reason for the same? We use 'int' for the similar parameter
> > > > recovery_min_apply_delay, so, ideally, it makes sense but still better to tell your
> > > > reason explicitly.
> > > Yes. It's because I thought I need to make this feature consistent with the recovery_min_apply_delay.
> > > This feature handles the range same as the recovery_min_apply delay from 0 to INT_MAX now
> > > so should be adjusted to match it.
> >
> > INT_MAX can stick out of int32 on some platforms. (I'm not sure where
> > that actually happens, though.) We can use PG_INT32_MAX instead.
> >
> 
> But in other integer GUCs including recovery_min_apply_delay, we use
> INT_MAX, so not sure if it is a good idea to do something different
> here.

The GUC is not stored in a catalog, but.. oh... it is multiplied by
1000. So if it is larger than (INT_MAX / 1000), it overflows...  If we
officially accept that (I don't think great) behavior (even only for
impractical values), I don't object further.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



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