User's Manual

U3585-J-Z125-8-76 455
Glossary
SDV (Start Device)
Instruction which initiates an input/output operation.
service times definition (DCS, I/O operations)
Detailed monitoring of service times is possible on XS systems with DCS, the interface
between the operating system, the I/O processor and the physical devices.
I/O chain
Start subchannel
Start I/O
Channel end
Interrupt accept
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