On Monday, 05/24/2010 at 11:02 EDT, TaeMin Baek <tmb...@kr.ibm.com> wrote:
> when i look at history data files in Perfomance Toolkits, too many Abort
of
> DASD Fast CCW translation occurs.
> anybody can explain why this is happen?
TaeMin, there really aren't "too many" aborts. There are *exactly* the
right number. While it is called an "abort", it should be called
"typical" CCW translation. "Fast" translation is used whenever possible
for some specific conditions.
Unfortunately we have a tendency to expose the internals (e.g. the name of
a field in a control block) in ways that make people nervous. ("Emergency
scan" anyone? It should really be "Scan 3".)
IIRC, having hw RESERVEs on the dasd will prevent use of fast ccw trans.
Alan Altmark
z/VM Development
IBM Endicott
