## 31.6. Monitoring

 Because logical replication is based on a similar architecture as [physical streaming replication](warm-standby.html#STREAMING-REPLICATION), the monitoring on a publication node is similar to monitoring of a physical replication primary (see [Section 27.2.5.2](warm-standby.html#STREAMING-REPLICATION-MONITORING)).

 The monitoring information about subscription is visible in [`pg_stat_subscription`](monitoring-stats.html#MONITORING-PG-STAT-SUBSCRIPTION). This view contains one row for every subscription worker. A subscription can have zero or more active subscription workers depending on its state.

 Normally, there is a single apply process running for an enabled subscription. A disabled subscription or a crashed subscription will have zero rows in this view. If the initial data synchronization of any table is in progress, there will be additional workers for the tables being synchronized.

