Classification: Confidential The practical statement is that velocity is a result, not an operand. The determined velocity is fed into the policy adjustment cycle.
The policy adjustment cycle will select 1 "donor" and 1 "receiver' each cycle (every 10 seconds last I heard. This determination is made by comparing the achieved velocity to the target velocity 2 pieces of work with the same velocity may get wildly different perceived performance. When everything is free, WLM has very little to do. When things are constrained, WLM will direct resources to the most important work as follows: SYSTEM Service Class SYSSTC Service Class IMP 1 through 5 work. (low to high) Discretionary work. There is really too much to answer in this question for a stream of emails. I hope this gets you started. Check out the "Systems Programmer Guide to WLM" for further information. Also GIYF. Check CMG, SHARE proceedings for additional practical information. HTH, -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Peter Sent: Monday, March 21, 2022 11:38 AM To: [email protected] Subject: Velocity in WLM - Clarification [CAUTION: This Email is from outside the Organization. Unless you trust the sender, Don’t click links or open attachments as it may be a Phishing email, which can steal your Information and compromise your Computer.] Hello, I must confess that I am new to WLMs. I have inherited an environment where the last update done in WLM was in the year 2001 and after that it was never changed. I have observed that the system address space is assigned with VELOCITY_80 and few ISV vendors applications are assigned with VELOCITY_40. Recently we had a situation where an ISV vendor's applications with VELOCITY_40 took more memory than the SYSTEM address space with VELOCITY_80. So, Here does it mean 40 velocity gets more importance than 80 velocity ? Or if I change all the system address space to have SYSSTC and will it impact the performance of ISV vendors application with 40 velocity ? Please shed some light on this, so that I can research further on this and tune my WLM policy. Peter ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ::DISCLAIMER:: ________________________________ The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. E-mail transmission is not guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or may contain viruses in transmission. The e mail and its contents (with or without referred errors) shall therefore not attach any liability on the originator or HCL or its affiliates. Views or opinions, if any, presented in this email are solely those of the author and may not necessarily reflect the views or opinions of HCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of authorized representative of HCL is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. Before opening any email and/or attachments, please check them for viruses and other defects. ________________________________ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
