Performance impact of QueryPerformanceCounter

Is there a performance impact from calling QueryPerforma开发者_C百科nceCounter over a less high-resolution timing method in Windows?

Although old, this Dr Dobb's article gives a nice summary of your options and their costs, pros and cons (see the tables right at the end), including QPC.

TBH, to get real timings for your situation, use a profiler (like AMD's CodeAnalyst) or something like Dr Fog's performance monitor(site, which also has some other things of use, depend how far you want to go into the hole of 'how much will this call/instruction/action cost').