Google adds cycle-level kernel profiling to XProf for TPU v7
Google added a Kernel Profiling suite to XProf (the OpenXLA/JAX profiler), exposing cycle-level details for custom kernels (e.g., Pallas) and sampling hardware performance counters on TPU v7 (Ironwood). The tooling shows lowered MLIR, per-unit time-aligned counter tracks, a Perf Counters view with ~16,000 raw counters, and supports periodic sampling (1µs floor) or external-triggered sub-microsecond capture; a Google demo using triple buffering reduced a matmul kernel from 125.5µs to 88µs.