we have an issue with our HP XL230a Gen9 blades where some of the applications are only seeing half of the CPU. On the task manager we see all 56 cores but application are only seeing half of them. We also see half CPU on NUMBER_OF_PROCESSORS=28 environment variable.
we enabled node interleaving in the BIOS and that fixed our issue i.e. all apps can see all 56 cores
The issue can be seen on both Hyperthreaded and Non hyperthreaded blades (windows 2008 r2 and windows 2012) and enabling node interleaving fixes the issue.
I found a C++ example which uses GetSystemInfo() and GetNativeSystemInfo() methods to get the available core and that too is showing only 28 when Node interleaving is disabled.
We have also applied the latest available firmware/bios update but still the same. We are contacting HP about this but just wanted to know if other people have seen anything like this and if there is a way to fix it with node interleaving=disabled?