You can do multiple concurrent rr recordings. A non-deterministic cpu bug would generally cause a divergence in the recording vs replay, so rr would be a decent

You can do multiple concurrent rr recordings. A non-deterministic cpu bug would generally cause a divergence in the recording vs replay, so rr would be a decent way to go about this. The way I'd have probably used rr when faced with this is to bisect the recording to find which code is responsible.