With DRAS 11.6 and earlier, the number of Maximum Users was in the range of 60 to 100 users. With CA VIEW 11.7 and CA DRAS 11.7, the number of maximum users can now exceed 500 up to a maximum of 1000 users, depending on region size.
Limits in Previous Releases
The maximum number of users that could access a Cross Memory region (XMS) or Distributed Repository Access System region (DRAS) was limited due to high usage of below-the-line storage which could exhaust available below-the-line storage at 60 to 100 users.
Limits at r11.7 and Above
Starting with Version r11.7, the below-the-line storage requirements are dramatically reduced. Certain data areas were moved to above-the-line storage and now share database related control areas.
The per user private and system below-the-line storage usage has been reduced to approximately 5 KB (kilobytes). Also private and system below-the-line storage related to allocation, open, and access of each database extent is approximately 2.5 KB.
If the region size (specified as REGION on the EXEC JCL statement or the system default region size) is large enough, these reductions allow the maximum number of users to exceed 500.
How to Calculate the Needed Region Size
At a minimum, allow 20 MB (megabytes) of REGION storage for the XMS and DRAS region plus 1 MB for every two users.
For 200 users
(20 MB + (200 users / 2)MB ) = 120 MB
Specify REGION=120M .
NOTE: Due to address space limits, the maximum amount of XMS users should not exceed 1000 users.
For more information, please see the CA View 11.7 Release Notes.