Logical replication blocking alter/drop

[Mark Fletcher <markf@xxxxxxxxxxxxxx>]

Hi All,

Postgres 9.6.5. We run several logical replication processes off our main postgres server. What we've noticed is that schema changes seem to block until we halt the logical replication processes. For example, I just did a 'DROP INDEX CONCURRENTLY' command, and it just sat there until I stopped the logical replication processes (I did not have to drop the logical replication slots).

Is this expected or are we perhaps doing something wrong?

Thanks,

Mark