set(value, labels, timestamp) {
		const hash = this.hashingLabels(labels);
		let item = this.values.get(hash);
		if (item) {
			if (value != item.value) {
				item.value = value;
				item.timestamp = timestamp == null ? Date.now() : timestamp;
				this.changed(value, labels, timestamp);
			}
		} else {
			item = {
				value,
				labels: pick(labels, this.labelNames),
				timestamp: timestamp == null ? Date.now() : timestamp
			};
			this.values.set(hash, item);
			this.changed(value, labels, timestamp);
		}

		return item;
	}
Set value.

@param {*} value
@param {Object?} labels
@param {Number?} timestamp
@returns
@memberof InfoMetric