  We propose an optical polariton clock based on the topologically protected
persistent oscillatory dynamics of a polariton superfluid, which is excited
non-resonantly by a super-Gaussian laser beam in a semiconductor microcavity
containing an external C-shape potential. The persistent oscillations,
characterised by a topological attractor, are based on the dynamical behavior
of small Josephson vortices rotating around the edge of the core of the central
vortex. The clock demonstrates a remarkable stability towards perturbations and
may be tuned by the pump laser intensity to two different frequency ranges:
20.16{\pm}0.14 GHz and 48.4{\pm}1.2 GHz. This clock generator is bistable due
to the chirality of the vortex.
