Critical Sections

In the Current Status (OLTP / liveCache) user menu, you can, among other things, obtain a display of the accesses to the main memory structures.

Procedure

       1.      Open the Database Assistant (transaction DB50) or the liveCache Assistant (transaction LC10).

       2.      Choose Current Status ® Critical Regions.

...

Result

The system displays an overview of the accesses to the main memory structures that are only used exclusively: critical regions (“synchronization objects” or “regions” which are managed by special semaphores). You can see which thread (task) is accessing the corresponding main memory structure.

You can use these statistics to determine cache activity and any resource conflicts that might exist. These conflicts can occur if a resource is requested more than once at a particular time.

If the number of conflicts is more than 10 % of all accesses, this indicates significant bottlenecks in your system.

Explanation of the OMS Synchronization Objects

Synchronization Object

Explanation

OMS2

Synchronization of the OMS heap

OMS3

Synchronization of the OMS monitor

OMS4

Synchronization of the unloading of versions

OMS5

Synchronization of the version directory

OMS6

Synchronization of the shared heap counter

OMS7

Synchronization of the stack heap counter

OMS8-OMS<n>

User-defined synchronization objects

See also:

Database Console