Gregory Haskins wrote:
Its more of an issue of execution latency (which translates to IO latency, since "execution" is usually for the specific goal of doing some IO). In fact, per my own design claims, I try to avoid exits like the plague and generally succeed at making very few of them. ;) So its not really the .4% reduction of cpu use that allures me. Its the 16% reduction in latency. Time/discussion will tell if its worth the trouble to use HC or just try to shave more off of PIO. If we went that route, I am concerned about falling back to MMIO, but Anthony seems to think this is not a real issue.
It's only a 16% reduction in latency if your workload is entirely dependent on the latency of a hypercall. What is that workload? I don't think it exists.
For a network driver, I have a hard time believing that anyone cares that much about 210ns of latency. We're getting close to the cost of a few dozen instructions here.
Regards, Anthony Liguori -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
