Tuning the UVCONFIG parameters for IBM InfoSphere Information Server Workload Management
Question
How do I tune the UVCONFIG parameters for IBM InfoSphere Information Server Workload Management to support running and queueing a large number of jobs
Answer
When IBM InfoSphere DataStage jobs are started or are queued, locks are created to prevent:
1. the deletion of the job while it is running or is in a queue.
2. the deletion of the project while the job is running or is in a queue.
The lock table size is defined by the RLTABSZ tunable in the UVCONFIG file.
The job also opens and reads status and run time information for the job from several dynamic hashed files. The dynamic hashed file handle limit is defined by the T30FILE tunable in the UVCONFIG file.
The default size for the lock table is 300 and the default limit for the file handle is 512.
With the default settings, approximately 150 jobs can be running and/or queued concurrently in the system.
To increased the number of jobs that can be running or queued, the RLTABSZ and T30FILE values
needs to be increased. The table below gives an example of values for a range of queue sizes.
| Maximum queue size / Maximum running jobs | T30FILE | RLTABSZ |
| 150 | 512 | 300 |
| 300 | 1024 | 375 |
| 600 | 2048 | 480 |
| 900 | 4096 | 480 |
As a general rule:
Maximum queue size = (T30FILE / 3) then the result is reduced by 10%
To change the value of T30FILE and RLTABSZ, follow this procedure:
1. Change directory to the IBM InfoSphere DataStage server directory.
The default location is /opt/IBM/InformationServer/Server/DSEngine.
2. Make a backup of the uvconfig file.
3. Stop IBM InfoSphere DataStage.
4. Edit the uvconfig file and set T30FILE and RLTABSZ to the new values, then run the command:
in Unix: bin/uv -admin -regen
in Windows: bin\uvregen
5. Restart IBM InfoSphere DataStage.