Re: Report the number of skipped frozen pages by manual VACUUM

On Thu, Mar 23, 2017 at 4:28 AM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
> On Wed, Mar 15, 2017 at 7:51 PM, Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
>> On Wed, Mar 15, 2017 at 1:09 PM, Yugo Nagata <nagata(at)sraoss(dot)co(dot)jp> wrote:
>>> On Fri, 10 Mar 2017 20:08:42 +0900
>>> Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
>>>
>>>> On Fri, Mar 10, 2017 at 3:58 PM, Jim Nasby <jim(dot)nasby(at)openscg(dot)com> wrote:
>>>> > On 3/6/17 8:34 PM, Masahiko Sawada wrote:
>>>> >>
>>>> >> I don't think it can say "1 frozen pages" because the number of
>>>> >> skipped pages according to visibility map is always more than 32
>>>> >> (SKIP_PAGES_THRESHOLD).
>>>> >
>>>> >
>>>> > That's just an artifact of how the VM currently works. I'm not a fan of
>>>> > cross dependencies like that unless there's a pretty good reason.
>>>>
>>>> Thank you for the comment.
>>>> Agreed. Attached fixed version patch.
>>>
>>> It seems that it says "frozen pages" if pinskipped_pages is not zero,
>>> rather than about frozenskipped_pages.
>>>
>>> How about writing as below?
>>>
>>> appendStringInfo(&buf, ngettext("Skipped %u page due to buffer pins, "
>>> "Skipped %u pages due to buffer pins, ",
>>> vacrelstats->pinskipped_pages),
>>> vacrelstats->pinskipped_pages);
>>> appendStringInfo(&buf, ngettext("%u frozen page.\n", "%u frozen pages.\n",
>>> vacrelstats->frozenskipped_pages),
>>> vacrelstats->frozenskipped_pages);
>>>
>>
>> Yeah, you're right. I've attached the updated version patch
>> incorporated your comment and fixing documentation.
>
> The patch looks very simple and good to me.
> Barring objection, I will commit this.

Pushed.

Regards,

--
Fujii Masao