On Monday, February 26, 2024 1:19 PM Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Fri, Feb 23, 2024 at 4:45 PM Bertrand Drouvot > <bertranddrouvot...@gmail.com> wrote: > > > > On Fri, Feb 23, 2024 at 09:46:00AM +0000, Zhijie Hou (Fujitsu) wrote: > > > > > > Besides, I'd like to clarify and discuss the behavior of > > > standby_slot_names > once. > > > > > > As it stands in the patch, If the slots specified in > > > standby_slot_names are dropped or invalidated, the logical walsender > > > will issue a WARNING and continue to replicate the changes. Another > > > option for this could be to have the walsender pause until the slot > > > in standby_slot_names is re-created or becomes valid again. Does anyone > else have an opinion on this matter ? > > > > Good point, I'd vote for: the only reasons not to wait are: > > > > - slots mentioned in standby_slot_names exist and valid and do catch > > up or > > - standby_slot_names is empty > > > > The reason is that setting standby_slot_names to a non empty value > > means that one wants the walsender to wait until the standby catchup. > > The way to remove this intentional behavior should be by changing the > > standby_slot_names value (not the existence or the state of the slot(s) it > points too). > > > > It seems we already do wait for the case when there is an inactive slot as > per the > below code [1] in the patch. So, probably waiting in other cases is also okay > and > also as this parameter is a SIGHUP parameter, users should be easily able to > change its value if required. Do you think it is a good idea to mention this > in > docs as well? > > I think it is important to raise WARNING as the patch is doing in all the > cases > where the slot is not being processed so that users can be notified and they > can > take the required action.
Agreed. Here is the V99 patch which addressed the above. This version also includes: 1. list_free the slot list when reloading the list due to GUC change. 2. Refactored the validate_standby_slots based on Shveta's suggestion. 3. Added errcode for the warnings as most of existing have errcodes. Amit's latest comments[1] are pending, we will address that in next version. [1] https://www.postgresql.org/message-id/CAA4eK1LJdmGATWG%3DxOD1CB9cogukk2cLNBGH8h-n-ZDJuwBdJg%40mail.gmail.com Best Regards, Hou zj
v99-0002-Document-the-steps-to-check-if-the-standby-is-re.patch
Description: v99-0002-Document-the-steps-to-check-if-the-standby-is-re.patch
v99-0001-Allow-logical-walsenders-to-wait-for-the-physica.patch
Description: v99-0001-Allow-logical-walsenders-to-wait-for-the-physica.patch
