Re: freeing bms explicitly

On Tue, Mar 22, 2022 at 8:45 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:

> On Tue, Mar 22, 2022 at 3:39 AM Zhihong Yu <zyu(at)yugabyte(dot)com> wrote:
> >
> > On Mon, Mar 21, 2022 at 3:05 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >>
> >> Zhihong Yu <zyu(at)yugabyte(dot)com> writes:
> >> >> I was looking at calls to bms_free() in PG code.
> >> >> e.g. src/backend/commands/publicationcmds.c line 362
> >> >> bms_free(bms);
> >> >> The above is just an example, there're other calls to bms_free().
> >> >> Since the bms is allocated from some execution context, I wonder why
> this
> >> >> call is needed.
> >> >>
> >> >> When the underlying execution context wraps up, isn't the bms freed ?
> >>
> >> Yeah, that's kind of pointless --- and the pfree(rfnode) after it is
> even
> >> more pointless, since it'll free only the top node of that expression
> >> tree. Not to mention the string returned by TextDatumGetCString, and
> >> whatever might be leaked during the underlying catalog accesses.
> >>
> >> If we were actually worried about transient space consumption of this
> >> function, it'd be necessary to do a lot more than this. It doesn't
> >> look to me like it's worth worrying about though -- it doesn't seem
> >> like it could be hit more than once per query in normal cases.
> >>
> >> regards, tom lane
> >
> >
> > Thanks Tom for replying.
> >
> > What do you think of the following patch ?
> >
>
> Your patch looks good to me. I have found one more similar instance in
> the same file and changed that as well accordingly. Let me know what
> you think of the attached?
>
> --
> With Regards,
> Amit Kapila.
>

Hi, Amit:
The patch looks good to me.

Cheers