Run results for: vwd streamer

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36

Browser: Chrome 60

Operating system: Mac OS X 10.12.6

Device Platform: Other

Date tested: 6 years ago

Test name	Executions per second
Origin code	979.7 Ops/sec
Optimized code	3172.8 Ops/sec

Script Preparation code:

var fields = [];

for (var i = 0; i < 1000; i++) {
    fields[i] = 'vwdId-' + i + '.vwdField';
}

// create duplications
fields = fields.concat(fields, fields);

Tests:

Origin code
var _streamerInstance = { _subscribe: function () {}, _unsubscribe: function () {}, _getCachedValue: function () {}, _update: function () {} }; var _subscribedFields = {}; var subscribe = function (fields) { if (!fields) { return } else if (typeof fields === "string") { fields = [fields] } var duplicateSubscriptions = []; for (var fieldIndex = 0; fieldIndex < fields.length; fieldIndex++) { var fieldName = fields[fieldIndex]; if (_subscribedFields[fieldName]) { duplicateSubscriptions.push(fieldIndex) } else { _subscribedFields[fieldName] = true } var cachedValue = _streamerInstance._getCachedValue(fieldName); if (cachedValue != null) { _streamerInstance._update(cachedValue.dataName, cachedValue.value, cachedValue.dataType, this) } } if (duplicateSubscriptions.length > 0) { fields = fields.slice(0); for (var i = duplicateSubscriptions.length - 1; i >= 0; i--) { fields.splice(duplicateSubscriptions[i], 1) } } _streamerInstance._subscribe(fields); } var unsubscribe = function (fields) { if (!fields) { return } else if (typeof fields === "string") { fields = [fields] } var invalidFields = []; for (var fieldIndex = 0; fieldIndex < fields.length; fieldIndex++) { var fieldName = fields[fieldIndex]; if (_subscribedFields[fieldName]) { delete _subscribedFields[fieldName] } else { invalidFields.push(fieldIndex) } } if (invalidFields.length > 0) { fields = fields.slice(0); for (var i = invalidFields.length - 1; i >= 0; i--) { fields.splice(invalidFields[i], 1) } } _streamerInstance._unsubscribe(fields); }; subscribe(fields); unsubscribe(fields);
Optimized code
var _streamerInstance = { _subscribe: function () {}, _unsubscribe: function () {}, _getCachedValue: function () {}, _update: function () {} }; var _subscribedFields = {}; var subscribe = function (fields) { if (!fields) { return } else if (typeof fields === "string") { fields = [fields] } var fieldsToSubscribe = []; var fieldsToSubscribeCount = 0; var length = fields.length; for (var fieldIndex = 0; fieldIndex < length; fieldIndex++) { var fieldName = fields[fieldIndex]; if (!_subscribedFields[fieldName]) { fieldsToSubscribe[fieldsToSubscribeCount] = fieldName; fieldsToSubscribeCount++; _subscribedFields[fieldName] = true } var cachedValue = _streamerInstance._getCachedValue(fieldName); if (cachedValue != null) { _streamerInstance._update(cachedValue.dataName, cachedValue.value, cachedValue.dataType, this) } } _streamerInstance._subscribe(fieldsToSubscribe); } var unsubscribe = function (fields) { if (!fields) { return } else if (typeof fields === "string") { fields = [fields] } var fieldsToUnsubscribe = []; var fieldsToUnsubscribeCount = 0; var length = fields.length; for (var fieldIndex = 0; fieldIndex < length; fieldIndex++) { var fieldName = fields[fieldIndex]; if (_subscribedFields[fieldName]) { fieldsToUnsubscribe[fieldsToUnsubscribeCount] = fieldName; fieldsToUnsubscribeCount++; delete _subscribedFields[fieldName] } } _streamerInstance._unsubscribe(fieldsToUnsubscribe); }; subscribe(fields); unsubscribe(fields);

Run results for: vwd streamer

Subscribe & Unsubscribe methods

Origin code

Optimized code