On Tue, 27 Nov 2007 13:27:08 -0800, Schuh, Richard <[EMAIL PROTECTED]> wrot e:
>Are the warnings about Limp Mode if there is no CRR machine still >extant? If so, there is still something being done by the CRR machine. >When lightly loaded, I would not expect it to be a problem. > > >Regards, >Richard Schuh DB2 definitely uses CRR, and possibly other applications. There are CRR c ommands that might tell you something, although I have not tried them. Limp Mode is still documented in "z/VM V5R3.0 Performance". If the CRR server is not running, users who use SFS (and other resources that participate in CRR) are in a condition called limp mode. While in this condition, two-phase c ommits are not possible. Therefore, applications that use protected conversations or other resourc es that do not support simple commit logic cannot be run. A user may experience significant SFS performance degradation while in limp mode. To avoid limp mode, IBM strongly recommen ds that every such system have the CRR server running. The generation of a CRR server (VMSER VR) and its associated file pool (VMSYSR) are optional z/VM installation tasks. The question is, when are two-phase commits used? From what others have t old you, one answer is when you have R/W access to two different SFS filepools. Alan Ackerman Alan (dot) Ackerman (at) Bank of America (dot) com
