  Quantum error correction is important to quantum information processing,
which allows us to reliably process information encoded in quantum error
correction codes. Efficient quantum error correction benefits from the
knowledge of error rates. We propose a protocol for monitoring error rates in
real time without interrupting the quantum error correction. Any adaptation of
the quantum error correction code or its implementation circuit is not
required. The protocol can be directly applied to the most advanced quantum
error correction techniques, e.g. surface code. A Gaussian processes algorithm
is used to estimate and predict error rates based on error correction data in
the past. We find that using these estimated error rates, the probability of
error correction failures can be significantly reduced by a factor increasing
with the code distance.
