Backend speed on windows

[Sahnvour]

Hi,

I'm curious about the best choice for speed concerns on windows-msvc.

I recall from reading various things on the internet and personal experience that dbghelp is quite slow, even if it's the preferred way.
From your experience, is that still the case ? Is there a difference with the winapi backend ?

Let's say for example that you needed to capture (not necessarily decode) tens of thousands of stacktraces per second. Would that be an issue ?

[jeremy-rifkin]

Hi,
From what I’ve seen dbghelp doesn’t seem horribly slow but tens of thousands of stack traces per second would be a pretty extreme use case.

There are two places dbghelp is used, there is an unwinding back-end using stackwalk64 and then it’s used form symbol resolution (for which dbghelp is the only option on windows).

Specifically for unwidning, stackwalk64 seems plenty fast from what I recall. I wouldn’t expect the winapi back-end using capturestackbacktrace to be any faster.

For your use-case, I would recommend collecting raw traces where you have performance requirements and resolving them at a later point. If you find resolution taking a while, cpptrace might be able to do some caching to help speed things up.