private void scheduleNextRequest(JRTClientConfigRequest jrtReq, JRTConfigSubscription<?> sub, long delay, long timeout) {
        long delayBeforeSendingRequest = (delay < 0) ? 0 : delay;
        JRTClientConfigRequest jrtReqNew = jrtReq.nextRequest(timeout);
        log.log(FINEST, timingValues::toString);
        log.log(FINE, () -> "Scheduling new request " + delayBeforeSendingRequest + " millis from now for " + jrtReqNew.getConfigKey());
        scheduler.schedule(new GetConfigTask(jrtReqNew, sub), delayBeforeSendingRequest, TimeUnit.MILLISECONDS);
    }
Requests the config for the {@link com.yahoo.config.ConfigInstance} on the given {@link ConfigSubscription}

@param sub a subscription
config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigRequester.java