To run multiple replications concurrently, you have two options:
Create a replication group
The advantage of this option is that you optimize database connections and, if you are mirroring data, optimize access to the transaction log. The transaction log is read only once per group, instead of once per replication where distinct reading threads would be generated that may also be scheduled and executed at different times. All replications in the group must have the same source and target connections. All replications are assigned the same scheduling properties, as well as mirroring/refresh properties, so you do lose some flexibility by grouping replications.Set individual replication properties so that the replications are scheduled together
For each replication, you need to set or edit the scheduling properties so that the replications are scheduled at the same time. This allows you to set separate mirroring/refresh properties for each replication and set a priority for each replication. With this option, you gain in flexibility but lose in performance when replications have a common source and target database connection.
Related Topics
Creating a Replication Group