FICON Express2 Channel Performance Version 1.0 - IBM

FICON Express2 Channel Performance Version 1.0
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response time components for 6x27K read
hits...162K bytes/io, 100% cu cache hit ratio
2Gbps Link Utilization(LU)
20% LU
30% LU
40% LU
50% LU
60% LU
70% LU
80% LU
90% LU
0 1 2 3 4 5
response times in ms
Figure 10
pend
conn
Figure 11 depicts the results of the 6x27K read/write mix benchmark where we achieve
270MB/sec by taking advantage of the full duplex capabilities of FICON links and
simultaneously processing some I/O’s that READ from DASD and some I/O’s that WRITE to
DASD. The 270 MB/sec achieved for this benchmark using FICON Express2 channels is
more than 50% higher than the maximum MB/sec that was achieved with the previous
generation FICON Express channels. The Full Duplex Link Utilizations (FDLU) plotted on
the 2nd y-axis in Figure 11 is calculated by dividing the sum of the READ + WRITE MB/sec
by 400 MB/sec which is the sum of the maximum instantaneous capabilities of the two
directional 2 Gigabit per second (Gbps) links that exist between the FICON Express2 channel
and the director port, where one 2 Gbps link transmits the commands and data frames from
the channel to the director and the other 2 Gbps link transfers the commands and data
frames in the opposite direction from the director to the channel.