Re: Introduce XID age and inactive timeout based replication slot invalidation - Mailing list pgsql-hackers

On Fri, Jan 31, 2025 at 5:50 PM Nisha Moond <nisha.moond412@gmail.com> wrote:
>
> Please find the attached v66 patch set. The base patch(v65-001) is
> committed now, so I have rebased the patches.
>

*
       <para>
         The time when the slot became inactive. <literal>NULL</literal> if the
-        slot is currently being streamed.
+        slot is currently being streamed. If the slot becomes invalidated,
+        this value will remain unchanged until server shutdown.
...
@@ -2408,7 +2527,9 @@ RestoreSlotFromDisk(const char *name)
  /*
  * Set the time since the slot has become inactive after loading the
  * slot from the disk into memory. Whoever acquires the slot i.e.
- * makes the slot active will reset it.
+ * makes the slot active will reset it. Avoid calling
+ * ReplicationSlotSetInactiveSince() here, as it will not set the time
+ * for invalid slots.
  */
  slot->inactive_since = GetCurrentTimestamp();

It looks inconsistent to set inactive_since on restart for invalid
slots but not at other times. We don't need to set inactive_since for
invalid slots. The invalid slots should not be updated. Ideally, this
should be taken care in the patch that introduces inactive_since but
we can do that now. Let's do this as a separate patch altogether in a
new thread.

--
With Regards,
Amit Kapila.