* @param <T> return type
     * @param operation the operation to execute
     * @return operation result
     * @throws CIFSException if circuit is open or operation fails
     */
    public <T> T executeWithCircuitBreaker(Supplier<T> operation) throws CIFSException {
        // Backpressure control
        if (backpressureEnabled && requestSemaphore != null) {
            if (!requestSemaphore.tryAcquire()) {