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• 句法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

静态 Atomics .notify() method notifies up some agents that are sleeping in the wait queue.

注意： This operation works with a shared Int32Array only.
It will return 0 on non-shared ArrayBuffer 对象。

句法

Atomics.notify(typedArray, index, count)
					

参数

typedArray

A shared Int32Array .

index

The position in the typedArray to wake up on.

count 可选

The number of sleeping agents to notify. Defaults to +Infinity .

返回值

• Returns the number of woken up agents.
• 返回 0 , if a non-shared ArrayBuffer object is used.

异常

• 抛出 TypeError , if typedArray is not a Int32Array .
• 抛出 RangeError , if index is out of bounds in the typedArray .

范例

使用 notify

Given a shared Int32Array :

const sab = new SharedArrayBuffer(1024);
const int32 = new Int32Array(sab);
					

A reading thread is sleeping and waiting on location 0 which is expected to be 0. As long as that is true, it will not go on. However, once the writing thread has stored a new value, it will be notified by the writing thread and return the new value (123).

Atomics.wait(int32, 0, 0);
console.log(int32[0]); // 123
					

A writing thread stores a new value and notifies the waiting thread once it has written:

console.log(int32[0]); // 0;
Atomics.store(int32, 0, 123);
Atomics.notify(int32, 0, 1);
					

规范

规范
ECMAScript (ECMA-262) The definition of 'Atomics.notify' in that specification.

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
notify	Chrome 68 68 不支持 60 — 63 Alternate Name Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This was a temporary removal while mitigations were put in place. Alternate Name Uses the non-standard name: wake	Edge 79	Firefox 78 78 63 Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog) . Disabled From version 63: this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 57 Alternate Name Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog) . Alternate Name Uses the non-standard name: wake Disabled From version 57: this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 不支持 55 — 57 不支持 48 — 55 Disabled Disabled From version 48 until version 55 (exclusive): this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 不支持 46 — 48 Alternate Name Disabled count parameter defaults to 0 instead of the later-specified +Infinity . Alternate Name Uses the non-standard name: futexWake Disabled ). To change preferences in Firefox, visit about:config.	IE No	Opera No	Safari 10.1 — 11.1 Alternate Name 不支持 10.1 — 11.1 Alternate Name Alternate Name Uses the non-standard name: wake	WebView Android 60 — 63 Alternate Name 不支持 60 — 63 Alternate Name Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This is intended as a temporary measure until other mitigations are in place. Alternate Name Uses the non-standard name: wake	Chrome Android 60 — 63 Alternate Name 不支持 60 — 63 Alternate Name Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This is intended as a temporary measure until other mitigations are in place. Alternate Name Uses the non-standard name: wake	Firefox Android 63 Disabled 63 Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog) . Disabled From version 63: this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 57 Alternate Name Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog) . Alternate Name Uses the non-standard name: wake Disabled From version 57: this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 不支持 55 — 57 不支持 48 — 55 Disabled Disabled From version 48 until version 55 (exclusive): this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 不支持 46 — 48 Alternate Name Disabled count parameter defaults to 0 instead of the later-specified +Infinity . Alternate Name Uses the non-standard name: futexWake Disabled ). To change preferences in Firefox, visit about:config.	Opera Android No	Safari iOS 10.3 — 11.3	Samsung Internet Android No Alternate Name 不支持 No Alternate Name Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This is intended as a temporary measure until other mitigations are in place. Alternate Name Uses the non-standard name: wake	nodejs 8.10.0 Alternate Name 8.10.0 Alternate Name Alternate Name Uses the non-standard name: wake

图例

完整支持

完整支持

不支持

不支持

见实现注意事项。

用户必须明确启用此特征。

用户必须明确启用此特征。

使用非标名称。

另请参阅

• Atomics
• Atomics.wait()

元数据

• 最后修改： Jul 7, 2020

相关话题

1. 标准内置对象
2. Atomics
3. 方法
   1. Atomics.add()
   2. Atomics.and()
   3. Atomics.compareExchange()
   4. Atomics.exchange()
   5. Atomics.isLockFree()
   6. Atomics.load()
   7. Atomics.notify()
   8. Atomics.or()
   9. Atomics.store()
   10. Atomics.sub()
   11. Atomics.wait()
   12. Atomics.xor()
4. 继承：
5. Object
6. 特性
   1. Object.prototype.__proto__
   2. Object.prototype.constructor
7. 方法
   1. Object.prototype.__defineGetter__()
   2. Object.prototype.__defineSetter__()
   3. Object.prototype.__lookupGetter__()
   4. Object.prototype.__lookupSetter__()
   5. Object.prototype.hasOwnProperty()
   6. Object.prototype.isPrototypeOf()
   7. Object.prototype.propertyIsEnumerable()
   8. Object.prototype.toLocaleString()
   9. Object.prototype.toSource()
   10. Object.prototype.toString()
   11. Object.prototype.valueOf()
   12. Object.setPrototypeOf()