On Fri, May 21, 2010 at 11:45 AM, Kris Buelens wrote:
> Rob, are you sure CP selects the channel to use? That was the case in the
> 370 era. AFAIK, in XA, CP will create a mask telling which channels *can*
> be used, but it is the IO subsystem that will select the channel and maybe
> even queue
Rob, are you sure CP selects the channel to use? That was the case in the
370 era. AFAIK, in XA, CP will create a mask telling which channels *can*
be used, but it is the IO subsystem that will select the channel and maybe
even queue the IO if all channels would be busy. In XA mode CP only queue
On Thu, May 20, 2010 at 3:39 PM, Billy Bingham
wrote:
> Hello all,
> Risking the old saying that it's better to have people think you're stupid
> than to open your mouth and remove all doubt :)
> If VM is doing I/O to one DASD volume only, say a DDR DUMP or RESTORE, and
> everything else is equal
Good question Billy, I'm waiting to see what the responses are !
In my environment, the SAD screen will show all 4 FICON channels to the DASD
with activity. What I don't
know is it VM balancing the load or the SAP engine doing the I/O. Inquiring
minds want to know ! LOL
Bubba
... snip
