Re: Separate out FileSet from SharedFileSet (was Re: pgsql: pgstat: Bring up pgstat in BaseInit() to fix uninitialized use o)

On Thu, Aug 26, 2021 at 11:47 AM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
>
> On Wed, Aug 25, 2021 at 5:49 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>>
>> On Tue, Aug 24, 2021 at 3:55 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
>> >
>> > On Tue, Aug 24, 2021 at 12:26 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>> >
>>
>> The first patch looks good to me. I have made minor changes to the
>> attached patch. The changes include: fixing compilation warning, made
>> some comment changes, ran pgindent, and few other cosmetic changes. If
>> you are fine with the attached, then kindly rebase the second patch
>> atop it.
>>
>
> The patch looks good to me,
>

Thanks, Sawada-San and Dilip for confirmation. I would like to commit
this and the second patch (the second one still needs some more
testing and review) for PG-15 as there is no bug per-se related to
this work in PG-14 but I see an argument to commit this for PG-14 to
keep the code (APIs) consistent. What do you think? Does anybody else
have any opinion on this?

Below is a summary of each of the patches for those who are not
following this closely:
Patch-1: The purpose of this patch is to refactor sharedfileset.c to
separate out fileset implementation. Basically, this moves the fileset
related implementation out of sharedfileset.c to allow its usage by
backends that don't want to share filesets among different processes.
After this split, fileset infrastructure is used by both
sharedfileset.c and worker.c for the named temporary files that
survive across transactions. This is suggested by Andres to have a
cleaner API and its usage.

Patch-2: Allow to use single fileset in worker.c (for the lifetime of
worker) instead of using a separate fileset for each remote
transaction. After this, the files to record changes for each remote
transaction will be created under the same fileset and the files will
be deleted after the transaction is completed. This is suggested by
Thomas to allow better resource usage.

--
With Regards,
Amit Kapila.