txn to pss ratio

txn to pss ratio determines the total number of transaction descriptors that are available to the server.

Summary Information

Default value


Valid values

1 – 2147483647



Display level


Required role

System administrator

Configuration groups

DTM Administration, Memory Use

SAP ASE manages transactions as configurable server resources. Each time a new transaction begins, SAP ASE must obtain a free transaction descriptor from a global pool that is created when the server is started. Transaction descriptors are internal memory structures that SAP ASE uses to represent active transactions.

SAP ASE requires one free transaction descriptor for:
At start-up, this ratio is multiplied by the number of PSS structures to create the transaction descriptor pool:
# of transaction descriptors = PSS structures * txn to pss ratio

The default value, 16, ensures compatibility with versions of SAP ASE earlier than 12.x which also allocated 16 transaction descriptors for each user connection. In version 12.x and later, the number of simultaneous transactions is limited only by the number of transaction descriptors available in the server.

Note: You can have as many databases in a user transaction as there are in your SAP ASE installation. For example, if your SAP ASE has 25 databases, you can include 25 databases in your user transactions.