Not a fair representation
As mentioned already by other comments, it's not really telling you anything sensible. The use of speedup rather than RMax is poor, this metric really doesn't tell you what you think it does, it assume Linpack is affected by network performance but it really isn't, and it's comparing two different hardware generations (the HPC system is running on CPUs that are at least 1 generation older than the Azure resources, and likely to be 2 generations old). Given linpack is really just a flop/s engine, you can't compare different generations of CPUs like this.
Biting the hand that feeds IT
