Tommy, The only problem I'm aware is that there may be an increase in CPU time for most programs and transactions the longer your system is up. I think this was first suggested by Cheryl Watson after a study back in the late 90s, and I confirmed that it was happening using SMF from an LPAR that had been up and running for a few months (six months I think). I do not remember how much increase there was.
I did hit an issue recently where I was purposely failing Storage Controllers and IO Drivers to the controller would just hang and need to be cancelled or forced off the system. After several week of this testing the CPU utilization of the LPAR had more than doubled while generating the same IO rate. We scheduled an IPL and everything was back to normal. It may worth choosing some sample workloads that run at all times of the day and track those over time to see if you are encountering any of these affects to the point that it is pushing your MSU charges up. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of > Tommy Tsui > Sent: Wednesday, September 02, 2009 6:09 PM > To: [email protected] > Subject: [IBM-MAIN] How often IPL a production LPAR (any good practice) > > Hi all, > > Is there any concern if we didn't IPL a LPAR over three months. Is there > any good practise to follow from IBM. They always replied LPAR never needs > IPL because of 24 x 7. > > Any comment will be appreciated > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- 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
