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Speculating on Zen 2 (Part 2)

This is the second part of my exploration into branch prediction and speculation in the Zen 2 microarchitecture, where we look at the behavior of unconditional direct branches and continue digging into details about the branch predictor.

Speculating on Zen 2 (Part 1)

This is the first part of my exploration into branch prediction and speculation in the Zen 2 microarchitecture, where I introduce a lot of context and present some tests with conditional branches.

Instrumenting PMCs on Zen 2 Machines

The last time I wrote, I talked about some of my experiments with the Instruction-based Sampling (IBS) functionality on Zen 2 machines. This time, we're talking about exploring something somewhat more general.

Playing with AMD IBS

A while ago, I built a new desktop machine with a Ryzen 9 3950X. I had never owned any AMD silicon before this, so I thought it might be kind of interesting to read the programmer's manual and learn a little bit about Zen 2.