We ran three tests to focus on the three main subsystems of the server -- CPU performance, network adapter performance and stack I/O performance.
The CPU test consists of SSL transactions triggered by Secure-HTTP requests sent from a Spirent Communications Avalanche 2700 for small files, about 1KB in size. The goal of this test is to load the CPU down with SSL encryption key calculations. The small file request reduces the load on the disk I/O and network subsystems.
The stack I/O subsystem test submits HTTP requests of small files to test TCP stack performance for how quickly it can set up and tear down TCP connections. As a control, the HTTP requests minimize the load on the CPU subsystem.
The network subsystem test executes HTTP requests of 0.5MB files. The goal of this test is to fully use the available network bandwidth of the server.
Many thanks to Spirent for use of its Avalanche test equipment and to IBM for technical support with its server.
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