On Friday, 10/01/2010 at 09:54 EDT, Tom Huegel <[email protected]> wrote: > Someone from our LINUX LAB asked me to trace 'TIMESTAMP' CCW's to mini-disks. > I never heard of a 'TIMESTAMP' CCW, but since most of my channel programming > knowledge dates back to preXA hardware I thought I would try to look it up in > the manuals. > After searching I could find nothing even suggesting there is a CCW command > that instructs the control unit to timestamp something. > Has anyone ever heard of such a thing? or be able to point me to some doc that > explains it. > If I sound vague it is because I am. This request has been translated through > no less that 3 languages (all "English").
According to documents on the web, timestamps are part of the PREFIX and DEFINE EXTENT CCWs. However, you will not find any documentation of PREFIX, nor of the extensions to DEFINE EXTENT (no pun intended). Another case of RTFC, as LINUX will use them. I think you need to move your tracing out of the realm of CCWs and consider whether Linux can trace the timestamps it is using in its I/O. Alan Altmark z/VM and Linux on System z Consultant IBM System Lab Services and Training ibm.com/systems/services/labservices office: 607.429.3323 [email protected] IBM Endicott
