In-band, on the fly allocation of tokens to a token bucket that limits the rate at which input/output operations are performed on a storage resource according to a maximum rate limit, while also supporting a user-configurable burst size limit that allows for a temporary spike in the rate input/output operations are received for the storage resource. An input/output time parameter is adjusted in response to receipt of input/output operations, based on the arrival times of the input/output operations, the maximum rate limit, and the burst size limit, in order to automatically allocate and consume tokens for the token bucket without requiring a separate token allocation thread.