On Fri, Dec 1, 2023 at 5:40 PM Nisha Moond <nisha.moond...@gmail.com> wrote: > > Review for v41 patch. > > 1. > ====== > src/backend/utils/misc/postgresql.conf.sample > > +#enable_syncslot = on # enables slot synchronization on the physical > standby from the primary > > enable_syncslot is disabled by default, so, it should be 'off' here. > > ~~~ > 2. > IIUC, the slotsyncworker's connection to the primary is to execute a > query. Its aim is not walsender type connection, but at primary when > queried, the 'backend_type' is set to 'walsender'. > Snippet from primary db- > > datname | usename | application_name | wait_event_type | backend_type > ---------+-------------+------------------+-----------------+-------------- > postgres | replication | slotsyncworker | Client | walsender > > Is it okay? > > ~~~ > 3. > As per current logic, If there are slots on primary with disabled > subscriptions, then, when standby is created it replicates these slots > but can't make them sync-ready until any activity happens on the > slots. > So, such slots stay in 'i' sync-state and get dropped when failover > happens. Now, if the subscriber tries to enable their existing > subscription after failover, it gives an error that the slot does not > exist.
Is this behavior expected? If yes, then is it worth documenting about disabled subscription slots not being synced? -- Thanks, Nisha
