max online engines

max online engines places an upper limit of the number of engine threads that can be brought online. It does not take into account the number of CPUs available at start-up, and allows users to add CPUs at a later date.

Summary Information

Default value


Range of values

1 – 1024 (threaded mode)

1 – 128 (process mode)



Display level


Required role

System administrator

Configuration groups

Memory Use, Processors

See System Administration Guide: Volume 2 > Managing Mulitprocessor Servers for a detailed discussion of how to set this parameter for your SMP environment.

The following is the sequence of events at SAP ASE start-up:

  1. System databases are recovered on engine 0.

  2. SAP ASE accepts user connections.

  3. All engines that are configured to be online during start-up are brought online.

  4. User databases are recovered in parallel by a “self-tuned” number of recovery tasks using the default data cache tuned for optimal recovery performance.

When tuning the max engines online parameter:

See Performance and Tuning Series: Basics > Using Engines and CPUs.