Optimizations For Microsoft's Hyper-V In Linux 4.14

Linux's support for the Microsoft Hyper-V hypervisor for server virtualization is seeing some performance tuning in the Linux 4.14 kernel.

This latest round of Hyper-V optimizations for Linux aren't coming from Microsoft engineers but rather a Red Hat developer. The Hyper-V optimization work includes faster hypercalls and faster TLB flushes.

Hyper-V hypercalls are made speedier in Linux 4.14 by supporting the "fast hypercall" implementation where parameters are passed through registers.

Related is now supporting "rep hypercalls" to perform multiple actions at once and a guarantee to return to the caller within 50 microseconds.

Lastly for making TLB flushes faster and better is using hypercalls for remote TLB flushes.

These Linux Hyper-V improvements landed with the x86-platform updates for the 4.14 kernel.