This is the modern version--based on Abseil--that we use in production for practically every C++ binary. It includes a number of performance optimizations (per-CPU caches, an improved fast/slow path, and a hugepage-aware backed), along with improved telemetry (a low overhead, always-on heap profiler, for example).

gperftools includes a decade+ old copy of TCMalloc and several other things (a signal-based CPU profiler, a heap checker, etc.). The two have diverged significantly.