On 2020-02-25 08:30, Antonin Houska wrote:
> I'm trying to figure out what's specific about RS_EPHEMERAL and RS_TEMPORARY
> slot kinds. The following comment (see definition of the
> ReplicationSlotPersistency enumeration) tells when each kind is dropped
The general idea is that an "ephemeral" slot is a future persistent slot
that is not completely initialized yet. If there is a crash and you
find an ephemeral slot, you can clean it up. The name is perhaps a bit
odd, you can think of it as an uninitialized one. A temporary slot is
one that behaves like a temporary table: It is removed at the end of a
session.
Perhaps the implementation differences are not big or are none, but it's
relevant for reporting. For example, the pg_replication_slots view
shows which slots are temporary. You wouldn't want to show an ephemeral
slot as temporary.
--
Peter Eisentraut http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
