At 2008-03-04 10:01, Gary Diehl <[EMAIL PROTECTED]> wrote about "Re: Setting up a service class for DDF" to IBM-Main:
> We also started years ago with one or two DDF service classes, [snip] > most effective has been to code a HI/MED/LOW setup [snip] each with > ONE and ONLY ONE service class period [snip] > We found that as DDF transactions moved from period to period, [snip] An extra item I'd like to point at is the type of DDF thread (Active vs. InActive modes) affects your goal choice/achievement. To quote the SysProgs guide to WLM RedBook (SG24-6472), "In Active mode the enclave is classified when it starts. If the enclave is reused by different work with different goals, all work is assigned to the goal of the enclave; that is, it is classified using the characteristic of the first work joining the enclave." and "Because threads that are always active do not terminate the enclave and thus do not reset the performance period to the first period, a long-running thread always ends up in the last performance period. Any new business units of work that use that thread will suffer the performance consequences. This makes performance periods unattractive for long-running threads. For always active threads, therefore, use velocity goals and use a single-period Service Class." 'course, *we're* still using Active DDF threads here; likely for historical reasons. However, the next time the DBAs & clients complain of response problems when some MS-Access thread decides to join & draw-down 15 entire tables, my first response will start, "Well, you know we could change our threads and ..." *grin* (The 2nd idea will be for them to decide which plans/packages should be moved to less aggressive Service Classes.) ----------> signature = 6 lines follows <-------------- Neil Duffee, Joe SysProg, U d'Ottawa, Ottawa, Ont, Canada telephone:1 613 562 5800 x4585 fax:1 613 562 5161 mailto:NDuffee of uOttawa.ca http:/ /aix1.uottawa.ca/ ~nduffee "How *do* you plan for something like that?" Guardian Bob, Reboot "For every action, there is an equal and opposite criticism." "Systems Programming: Guilty, until proven innocent" John Norgauer 2004 ---------------------------------------------------------------------- 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
