[jdsully]

Yes default settings. The code we’re talking about is a hand rolled LZF decompressor originally written on the Ryzen 9 (so not intentionally Intel optimized).

Spectre doesn’t make much difference since its not making syscalls.

If you can somehow keep the CPU fed it becomes obvious there is more oomph behind the Intel device. That said how often are you running hand rolled assembly routines?

As an additional datapoint liblzf is faster on the Ryzen. But its limited by pipeline stalls so doesn’t get to take advantage of the extra resources.