Re: add log messages when replication slots become active and inactive (was Re: Is it worth adding ReplicationSlot active_pid to ReplicationSlotPersistentData?)

On Fri, Mar 24, 2023 at 3:11 AM Euler Taveira <euler(at)eulerto(dot)com> wrote:
>
> If you are adding separate functions as suggested, you should add a comment at
> the top of ReplicationSlotAcquire() and ReplicationSlotRelease() functions
> saying that LogReplicationSlotAquired() and LogReplicationSlotReleased()
> functions should be called respectively after it.

Done.

> My suggestion is that the functions should have the same name with a "Log"
> prefix. On of them has a typo "Aquired" in its name. Hence,
> LogReplicationSlotAcquire() and LogReplicationSlotRelease() as names. It is
> easier to find if someone is grepping by the origin function.

Done.

> I prefer a sentence that includes a verb.
>
> physical replication slot \"%s\" is acquired
> logical replication slot \"%s\" is released

Hm, changed for now. But I'll leave it to the committer's discretion.

> Isn't the PID important for this use case? If so, of course, you can rely on
> log_line_prefix (%p) but if the PID is crucial for an investigation then it
> should also be included in the message.

On Fri, Mar 24, 2023 at 3:10 AM Peter Smith <smithpb2250(at)gmail(dot)com> wrote:
>
> Patch v8 applied OK, and builds/renders the HTML docs OK, and passes
> the regression and subscription TAP tests OK.
>
> Here are some minor comments:
>
> 1.
> + ereport(log_replication_commands ? LOG : DEBUG3,
> + (errmsg("acquired physical replication slot \"%s\"",
> + slotname)));
>
> AFAIK those extra parentheses wrapping the "errmsg" part are not necessary.

Done

> 2.
> extern void LogReplicationSlotAquired(bool is_physical, char *slotname);
> extern void LogReplicationSlotReleased(bool is_physical, char *slotname);
>
> The "char *slotname" params of those helper functions should probably
> be declared and defined as "const char *slotname".

Done.

> Otherwise, from a code review perspective the patch v8 LGTM.

Thanks. Please have a look at the v9 patch.

--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com