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Figure 3-11 shows the measured CPU times, general CP (bar in bold) and zIIP (bar that uses the pattern) for different combinations of processors for SMT-1 and SMT-2 scenarios that use the same workload. 

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For configurations that used 1 - 4 zIIPs, the CP CPU time (which is chargeable) is less when SMT-2 is enabled for the zIIP engines. After all zIIP eligible processing is offloaded for SMT-1, no difference in CP CPU time between SMT-1 and SMT-2 was observed, as expected. 

