In addition to the previous comments, there are some potential advantages to HiperSockets when considering workload portability. You may be able to ignore some OSA-Express physical and logical configuration considerations for inter-LPAR communications on, for example, a DR machine. That could simplify DR procedures and thus make DR more robust, in certain cases anyway.
I too recommend adopting SMC-D as soon as reasonably practical. SMC-D is not a complete replacement for HiperSockets (or for OSA-Express connections). However, implementing HiperSockets is a common step on the journey to implementing SMC-D, even if you're not immediately ready to implement SMC-D. HiperSocket connections need not replace OSA-Express connections when both network paths are available. You can choose one, the other, or both inter-LPAR connectivity options, selectively and opportunistically, subsystem by subsystem, application by application. For example, you can choose the HiperSocket path when low latency is most important. Yes, HiperSockets require a modest amount of central processor attention when there is HiperSocket activity. However, for many (or even most) workloads the latency reduction yields CPU savings. So even if you *only* care about CPU utilization (you shouldn't), you may still be better off using HiperSockets. You can make such evaluations and decisions selectively, as noted in the previous paragraph. HiperSockets can make certain workloads (and LPAR splits) that were practically impossible possible, particularly certain batch workloads that have to (or should) cross LPAR boundaries during their execution but also occasionally online transactions with tight response time limits. HiperSockets may allow you to reduce the number of OSA-Express adapters in your machine -- or at least to avoid increasing the number of adapters in the future. Or, said another way, with HiperSockets the genuinely external network traffic doesn't have to compete with inter-LPAR traffic for OSA-Express resources. HiperSockets offer some inherent security advantages. Good stuff, those HiperSockets. -------------------------------------------------------------------------------------------------------- Timothy Sipples IT Architect Executive, Industry Solutions, IBM z Systems, AP/GCG/MEA E-Mail: [email protected] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
