A parameter determining how long a standby should wait before canceling queries that conflict with WAL
max_standby_archive_delay is a configuration parameter determining how long a standby server should wait before canceling queries that conflict with pending WAL entries received via archive recovery.
max_standby_archive_delay was added in PostgreSQL 9.0.
max_standby_streaming_delay were added in place of
max_standby_delay, which was added earlier in the PostgreSQL 9.0 release cycle (commit efc16ea5).