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The workload measurement results from a normalized throughput perspective are shown in Figure 3-9. Normalized throughput is the throughput rate (in transactions per second) that are normalized out to 100% CPU usage, which is also known as the Internal Throughput Rate (ITR). 

<img src='content_image/973061.jpg'>

The normalized throughput rate shows a 25.64% increase when SMC-D is used compared to HiperSockets, and a 10.23% increase compared to OSA 10 Gb. This results provides some insight into CPU time savings on per-transaction basis. 

Customers that use an BM z13 GA2 or z13s and z/OS Version 2.2 that have Db2 workloads (such as SQLJ IRWW) that require communication between LPARs on the same CEC, can greatly benefit from the use of SMC-D. The combined hardware and software solution provides improved transaction rates, significantly reduced network latency, and lower CPU cost. 

## 3.3 Simultaneous multithreading 

With the introduction of the z13 machine, IBM implemented simultaneous multithreading (SMT-2), which enables two active instructions per processor core. This feature can improve the processing capacity per processor core when more than one task is running. SMT-2 is available for workloads that are running on the Integrated Facility for Linux (IFL) and workloads that use the z Integrated Information Processor (zIIP). SMT-2 also requires operating system support by z/OS (for zIIP usage) and IBM z/VMfi (for IFL usage). 

For more information about SMT-2, see the following resources: 

GLYPH<SM590000> z Systems Simultaneous Multithreading Revolution , REDP-5144 

GLYPH<SM590000> IBM z13 Technical Guide , SG24-8251 

