Wow, someone else! We have a full production implementation and we just discovered this too. We're having those discussions with IBM now.
Marcy "This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose, or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation." -----Original Message----- From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Tobias Doerkes Sent: Friday, March 05, 2010 3:32 AM To: IBMVM@LISTSERV.UARK.EDU Subject: [IBMVM] GDPS xDR, I/O-Timing and MIH this mail is crossposted to IBMVM and LINUX-390 hi lists, we are a GDPS shop for several years. recently we implemented GDPS xDR in our sandbox environment. now we found out that there is a different handling of MIH and I/O-Timing in z/VM as it is in z/OS. in case the MIH time is reached in z/OS the I/O is redriven as often as I/O timing is reached - roughly speaking. After reaching I/O timing limit the I/O is given back to the application with an error. in an GDPS environment i can choose wether I/O-Timing is a hyperswap trigger or not. in z/VM I/O-Timing and MIH are the same value. if MIH is reached and hyperswap is enabled, this situation is a hyperswap trigger. No differentiation, no recovery, no retry - nothing. so my question is wether you have MITIME=OFF in z/VM or which value did you choose in case your installation is xDR enabled? if IBM would ask me, i would suggest that the handling in z/OS and z/VM should be the same. tobias doerkes. _________________________________________________________________ Hotmail: Powerful Free email with security by Microsoft. https://signup.live.com/signup.aspx?id=60969
