react-native/Libraries/Utilities/PerformanceLogger.js

197 lines
4.5 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @flow
* @format
*/
'use strict';
const Systrace = require('Systrace');
const infoLog = require('infoLog');
const performanceNow =
/* $FlowFixMe(>=0.54.0 site=react_native_oss) This comment suppresses an
* error found when Flow v0.54 was deployed. To see the error delete this
* comment and run Flow. */
global.nativeQPLTimestamp ||
global.nativePerformanceNow ||
require('fbjs/lib/performanceNow');
type Timespan = {
description?: string,
totalTime?: number,
startTime?: number,
endTime?: number,
};
let timespans: {[key: string]: Timespan} = {};
let extras: {[key: string]: any} = {};
const cookies: {[key: string]: number} = {};
const PRINT_TO_CONSOLE: false = false; // Type as false to prevent accidentally committing `true`;
/**
* This is meant to collect and log performance data in production, which means
* it needs to have minimal overhead.
*/
const PerformanceLogger = {
addTimespan(key: string, lengthInMs: number, description?: string) {
if (timespans[key]) {
if (__DEV__) {
infoLog(
'PerformanceLogger: Attempting to add a timespan that already exists ',
key,
);
}
return;
}
timespans[key] = {
description: description,
totalTime: lengthInMs,
};
},
startTimespan(key: string, description?: string) {
if (timespans[key]) {
if (__DEV__) {
infoLog(
'PerformanceLogger: Attempting to start a timespan that already exists ',
key,
);
}
return;
}
timespans[key] = {
description: description,
startTime: performanceNow(),
};
cookies[key] = Systrace.beginAsyncEvent(key);
if (PRINT_TO_CONSOLE) {
infoLog('PerformanceLogger.js', 'start: ' + key);
}
},
stopTimespan(key: string) {
const timespan = timespans[key];
if (!timespan || !timespan.startTime) {
if (__DEV__) {
infoLog(
'PerformanceLogger: Attempting to end a timespan that has not started ',
key,
);
}
return;
}
if (timespan.endTime) {
if (__DEV__) {
infoLog(
'PerformanceLogger: Attempting to end a timespan that has already ended ',
key,
);
}
return;
}
timespan.endTime = performanceNow();
timespan.totalTime = timespan.endTime - (timespan.startTime || 0);
if (PRINT_TO_CONSOLE) {
infoLog('PerformanceLogger.js', 'end: ' + key);
}
Systrace.endAsyncEvent(key, cookies[key]);
delete cookies[key];
},
clear() {
timespans = {};
extras = {};
if (PRINT_TO_CONSOLE) {
infoLog('PerformanceLogger.js', 'clear');
}
},
clearCompleted() {
for (const key in timespans) {
if (timespans[key].totalTime) {
delete timespans[key];
}
}
extras = {};
if (PRINT_TO_CONSOLE) {
infoLog('PerformanceLogger.js', 'clearCompleted');
}
},
clearExceptTimespans(keys: Array<string>) {
timespans = Object.keys(timespans).reduce(function(previous, key) {
if (keys.indexOf(key) !== -1) {
previous[key] = timespans[key];
}
return previous;
}, {});
extras = {};
if (PRINT_TO_CONSOLE) {
infoLog('PerformanceLogger.js', 'clearExceptTimespans', keys);
}
},
currentTimestamp() {
return performanceNow();
},
getTimespans() {
return timespans;
},
hasTimespan(key: string) {
return !!timespans[key];
},
logTimespans() {
for (const key in timespans) {
if (timespans[key].totalTime) {
infoLog(key + ': ' + timespans[key].totalTime + 'ms');
}
}
},
addTimespans(newTimespans: Array<number>, labels: Array<string>) {
for (let ii = 0, l = newTimespans.length; ii < l; ii += 2) {
const label = labels[ii / 2];
PerformanceLogger.addTimespan(
label,
newTimespans[ii + 1] - newTimespans[ii],
label,
);
}
},
setExtra(key: string, value: any) {
if (extras[key]) {
if (__DEV__) {
infoLog(
'PerformanceLogger: Attempting to set an extra that already exists ',
{key, currentValue: extras[key], attemptedValue: value},
);
}
return;
}
extras[key] = value;
},
getExtras() {
return extras;
},
logExtras() {
infoLog(extras);
},
};
module.exports = PerformanceLogger;