WLM and skip clock
(Cross posted) Esteemed listers In some past posts, while discussing about WLM, someone introduced 'skip clock' concept to describe behaviour of wlm when goals are not reached, for instance because they are quite high and there isn't enough to boost them. In this case wlm ignores them (or leaves them with reached velocity) until skip clock expires (so I was told). Is this skip clock concept described somewhere (manuals, papers ) ? Thank you in advance Max Scarpa Db2 sysprog -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: WLM and skip clock
In some past posts, while discussing about WLM, someone introduced 'skip clock' concept to describe behaviour of wlm when goals are not reached, for instance because they are quite high and there isn't enough to boost them. In this case wlm ignores them (or leaves them with reached velocity) until skip clock expires (so I was told). Is this skip clock concept described somewhere (manuals, papers ) ? Check out the WLM Services manual in the Chapter Using SMF Record Type 99. It's not discussed heavily, but it indicates its use. Adam -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: WLM and skip clock
On Wed, 9 Jul 2008 08:12:39 -0500, Max Scarpa [EMAIL PROTECTED] wrote: (Cross posted) Esteemed listers In some past posts, while discussing about WLM, someone introduced 'skip clock' concept to describe behaviour of wlm when goals are not reached, for instance because they are quite high and there isn't enough to boost them. In this case wlm ignores them (or leaves them with reached velocity) until skip clock expires (so I was told). Is this skip clock concept described somewhere (manuals, papers ) ? Other than a mention of it in the SMF 99 description, I don't think so. Many of the WLM internals are not. I remember seeing something about this in the (now old) OS/390 Workload Manager Implementation and Exploitation Redbook (SG24-5326-00)... although it didn't say it was the skip clock. The same thing is in the current Redook System Programmers Guide to: Workload Manager (SG24-6472-03): Periods for certain service classes are not candidates for being a receiver because in the past they were defined as receivers without much improvement in their PI. Those service class periods are skipped for a while to avoid wasting effort. This usually only happens when the installation sets a very difficult goal. Regards, Mark -- Mark Zelden Sr. Software and Systems Architect - z/OS Team Lead Zurich North America / Farmers Insurance Group - ZFUS G-ITO mailto:[EMAIL PROTECTED] z/OS Systems Programming expert at http://expertanswercenter.techtarget.com/ Mark's MVS Utilities: http://home.flash.net/~mzelden/mvsutil.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: WLM and skip clock
Hi Adam I've found it, thank you very much Max Scarpa -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: WLM and skip clock
In some past posts, while discussing about WLM, someone introduced 'skip clock' concept to describe behaviour of wlm when goals are not reached, for instance because they are quite high and there isn't enough to boost them. In this case wlm ignores them (or leaves them with reached velocity) until skip clock expires (so I was told). Is this skip clock concept described somewhere (manuals, papers ) ? From the WLM Services: They are also skipped when a potential receiver's skip clock hasn't expired. If a receiver is assessed and all actions to help it are rejected, a skip clock (counter) is set and the service class period will not be selected as a receiver again until the skip clock expires. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: WLM and skip clock
Hi Mark, thank you for your reply I read it in redbook as well but as you said there's no 'direct' reference to skip clock concept, only a generic delay (skip) as it was considered useless to help that workload due to unattainable goals. Best regards Max Scarpa -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
