Critical Path Optimization in mainframes.

[Leena]

Hi,

How do we approach to Critical Path Optimization in mainframes? Can someone please guide me with his experience on this?

[Leena]

I ask this question as one of the other team in our project is supposed to get this done though they don't understand it themselves. While searching on the internet I get to see this link https://www1.jobdiva.com/candidates/myj ... ivisions2=

and there they use it also like this," The SME will lead the Critical Path Optimization program, MIPS Reduction Program, and manage the Mainframe source repository team with the goal of delivering stability, manageability and cost saving." So it is somehitng.

[Robert Sample]

First, you start by reading the Redbook SG24-4816 Approaches to Optimize Batch Processing on z/OS.

Second, you learn the batch jobs REALLY well.

Third, you use the techniques in the Redbook to look at how the batch processing is set up and whether or not changes could reduce the elapsed time for the batch window. Sometimes, merely changing a few job start times can reduce the window; other times, reducing the batch window requires significant investment (such as acquiring faster hardware). The specifics, as usual, depend upon the site.

[Leena]

Thank you Robert. It's a big process that's what I understand and there is a "series of batch jobs" which are called as "critical path" for a given business. I thought it was universal across different companies.

[Robert Sample]

In project management, the critical path is the workflow which determines the length of time the project will take -- any delay in the critical path tasks means the entire project will be delayed. If a task is not on the critical path, it has slack time (which is, basically, the amount of time before the task becomes part of the critical path). Any delay in such a task, as long as the delay is less than the slack time, will have no impact upon the project completion. This terminology is common to project management and applies no matter what the company is.

Critical path optimization is looking at a batch job flow to determine if (and how) the total elapsed time can be reduced. Many companies do this (some regularly, some only when needed). What varies from company to company is the actions that can be taken -- for one company with an 8-hour critical path and a data base update job that runs all 8 hours, there's not much they can do to shorten the critical path other than working to redesign the data base or redo the update program; for another company where the 8-hour critical path has 8 one-hour jobs, they may be able to adjust the dependencies so half the jobs can run in parallel, which would cut 2 to 3 hours from the critical path.