AB379B - PCI-X Dual Channel 4Gb/s Fibre Channel Adapter Performance Paper for Integrity Servers
5
Throughput
AB379B offers excellent throughput capabilities with large size I/O operations. Service demand is the amount
of CPU utilized per megabyte of data transferred. To measure throughput of the AB379B, 256KB sequential
read and write operations were performed on the 8-way rx6600 system.
Chart 2a: Single and Dual Port Throughput Chart 2b: CPU Utilization for Throughput tests
Chart 2a shows the 256KB sequential read, write, and bidirectional throughput of single and dual ports of the
AB379B. The X-axis is the number of Fibre Channel ports. The Y-axis is the throughput in MB/s.
As chart 2a shows, one port of the AB379B performs reads or writes at 410 MB/s. Two ports of the AB379B
scale at 2x the performance of a single port, performing read or write operations at 820 MB/s. Bidirectional
throughput scales at nearly 2x the performance of unidirectional reads or writes.
Chart 2a demonstrates outstanding read, write, and bidirectional performance with linear scaling for 1 and 2
ports of the AB379B.
Chart 2b shows the % CPU utilization of the throughput tests. These tests are performed on the rx6600 with
8 CPUs. The X-axis is the number of the Fibre Channel ports. The Y-axis is the percentage of the 8 CPUs utilized
by the particular test. Chart 2b shows very low CPU utilization for single and dual ports in read, write, and
bidirectional throughput tests.
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2
00
4
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6
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8
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1
0
00
Number of Ports
Throughput
–
MB/s
(10
^6 bytes/sec)
Therotical Max
410
820
Read
410
820
Write
410
820
1
2
1200
1400
1600
Bidirectional
808
16
15
0
.2
.4
.6
.8
1.0
1.2
1.4
1.6
Number of Ports
% CPU Utilization
*
Read
0.6%
1.1%
Write
0.6%
1.1%
1
2
*
aggregate CP
U
utilization % across the 8 CPUs
Bidir
1.1%
2.4%
1.8
2.0
2.2
2.4