Yeah I was expecting the uninitialized to be the same as the zeroed case for that reason, but was surprised to see a (slightly) different result.
Edit: you are almost certainly right. I added a getrusage call before and after, and we have ~50k soft page faults in the uninitialized case and ~2 in the zeroed case during the memmem.
Edit: you are almost certainly right. I added a getrusage call before and after, and we have ~50k soft page faults in the uninitialized case and ~2 in the zeroed case during the memmem.