622 Adapters

Performance Report on ATM adapters 5

The MTU size makes a difference in the scalability. See Table 6 below.

Table 6: Maximum TCP Throughput and Interface Type on K580 (four CPUs, six 155 Adapters)

Classical IP

MTU 9180 bytes

LANE

MTU 9218 bytes

LANE

MTU 1516 bytes

Outbound Mbps 654 611 247

Inbound Mbps 589 589 252

Bidirectional Mbps 666 584 249

The maximum throughput and request/response performance on the K580 is shown in Table 7

below. The figures compare the performance when using six 155 adapters versus four 622

adapters.

Table 7: K580 (four CPUs): Maximum Figures for 155 and 622 adapters

The request/response performance is CPU bound. To get an additional transaction rate, it is

better to add/allocate CPU resources instead of adding adapters.

six 155 adapters four 622 adapters

Outbound TCP Throughput Mbps 654.19 812.96

CPU Utilization % 76.59 86.43

Bidirectional TCP Throughput Mbps 666 820.11

CPU Utilization % 85.8 83.92

TCP Single byte R/R Transactions/sec 22432 30296

CPU Utilization % 100 100

UDP (1K/2K) R/R Transactions/sec 15696 19579

CPU Utilization % 100 100