FICON Administrator's Guide v6.4.0 (53-1001771-01, June 2010)

FICON Administrator’s Guide 39
53-1001771-01
FICON emulation overview
4
Tape Write Pipelining
FICON tape write pipelining improves performance for a variety of applications when writing to tape
over extended distances. FICON tape write pipelining locally acknowledges write data records,
enabling the host to generate more records while previous records are in transit across the IP WAN.
If an exception status is received from the device, the writing of data and emulation is terminated.
FIGURE 11 Tape Write Pipelining
Tape Read Pipelining
FICON Tape Read Pipelining improves performance for certain applications when reading from
FICON tape over extended distances. FICON Tape Read Pipelining reads data on the tape directly
from the tape device. Reading of the tape continues until a threshold is reached. The buffered data
is forwarded to the host in response to requests from the host. When the host sends the status
accept frame indicating that the data was delivered, the read processing on the device side credits
the pipeline and requests more data from the tape. If an exception status is received from the
device, the reading of data and emulation is terminated.