From 33058f2b292b3a581333bdfb21b8f671898c5060 Mon Sep 17 00:00:00 2001 From: Peter Bengtsson Date: Tue, 8 Dec 2020 14:40:17 -0500 Subject: initial commit --- .../hardwareconcurrency/index.html | 69 +++++++++++++++++++++ .../web/api/navigatorconcurrenthardware/index.html | 71 ++++++++++++++++++++++ 2 files changed, 140 insertions(+) create mode 100644 files/zh-cn/web/api/navigatorconcurrenthardware/hardwareconcurrency/index.html create mode 100644 files/zh-cn/web/api/navigatorconcurrenthardware/index.html (limited to 'files/zh-cn/web/api/navigatorconcurrenthardware') diff --git a/files/zh-cn/web/api/navigatorconcurrenthardware/hardwareconcurrency/index.html b/files/zh-cn/web/api/navigatorconcurrenthardware/hardwareconcurrency/index.html new file mode 100644 index 0000000000..806e40fbec --- /dev/null +++ b/files/zh-cn/web/api/navigatorconcurrenthardware/hardwareconcurrency/index.html @@ -0,0 +1,69 @@ +--- +title: navigator.hardwareConcurrency +slug: Web/API/NavigatorConcurrentHardware/hardwareConcurrency +translation_of: Web/API/NavigatorConcurrentHardware/hardwareConcurrency +--- +

{{APIRef("HTML DOM")}}

+ +

{{AvailableInWorkers}}

+ +

navigator.hardwareConcurrency 指明当前浏览器环境所拥有的CPU核心数，这来自于操作系统提供的API来获取。

+ +

用法

+ +
CPU核心数= window.navigator.hardwareConcurrency
+
+ +

Value

+ +

A {{jsxref("Number")}} indicating the number of logical processor cores.

+ +

Modern computers have multiple physical processor cores in their CPU (two or four cores is typical), but each physical core is also usually able to run more than one thread at a time using advanced scheduling techniques. So a four-core CPU may offer eight logical processor cores, for example. The number of logical processor cores can be used to measure the number of threads which can effectively be run at once without them having to context switch.

+ +

The browser may, however, choose to report a lower number of logical cores in order to represent more accurately the number of {{domxref("Worker")}}s that can run at once, so don't treat this as an absolute measurement of the number of cores in the user's system.

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Examples

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In this example, one {{domxref("Worker")}} is created for each logical processor reported by the browser and a record is created which includes a reference to the new worker as well as a Boolean value indicating whether or not we're using that worker yet; these objects are, in turn, stored into an array for later use. This creates a pool of workers we can use to process requests later.

+ +
let workerList = [];
+
+for (let i = 0; i < window.navigator.hardwareConcurrency; i++) {
+  let newWorker = {
+    worker: new Worker('cpuworker.js'),
+    inUse: false
+  };
+  workerList.push(newWorker);
+}
+ +

Specification

+ + + + + + + + + + + + + + +
SpecificationStatusComment
{{SpecName('HTML WHATWG', '#navigatorconcurrenthardware', 'NavigatorConcurrentHardware')}}{{Spec2('HTML WHATWG')}}Initial definition.
+ +

Browser compatibility

+ +
+ + +

{{Compat("api.NavigatorConcurrentHardware.hardwareConcurrency")}}

+
+ +

See also

+ + diff --git a/files/zh-cn/web/api/navigatorconcurrenthardware/index.html b/files/zh-cn/web/api/navigatorconcurrenthardware/index.html new file mode 100644 index 0000000000..d7cee835c0 --- /dev/null +++ b/files/zh-cn/web/api/navigatorconcurrenthardware/index.html @@ -0,0 +1,71 @@ +--- +title: NavigatorConcurrentHardware +slug: Web/API/NavigatorConcurrentHardware +tags: + - API + - Concurrency + - HTML DOM + - Interface + - Navigator + - NavigatorCPU + - NavigatorConcurrentHardware + - NeedsBrowserCompatibility + - NeedsTranslation + - Reference + - Threading + - Threads + - TopicStub + - WorkerNavigator + - Workers +translation_of: Web/API/NavigatorConcurrentHardware +--- +

{{APIRef("HTML DOM")}}

+ +

The NavigatorConcurrentHardware {{Glossary("mixin")}} adds to the {{domxref("Navigator")}} interface features which allow Web content to determine how many logical processors the user has available, in order to let content and Web apps optimize their operations to best take advantage of the user's CPU.

+ +

{{AvailableInWorkers}}

+ +

The number of logical processor cores is a way to measure the number of threads which can effectively be run at once without them having to share CPUs. Modern computers have multiple physical cores in their CPU (two or four cores is typical), but each physical core is also usually able to run more than one thread at a time using advanced scheduling techniques. So a four-core CPU may return 8. The browser may, however, choose to reduce the number in order to represent more accurately the number of {{domxref("Worker")}}s that can run at once

+ +

Properties

+ +
+
{{domxref("NavigatorConcurrentHardware.hardwareConcurrency")}} {{readonlyinline}}
+
Returns the number of logical processors which may be available to the user agent. This value is always at least 1, and will be 1 if the actual number of logical processors can't be determined.
+
+ +

Methods

+ +

The NavigatorConcurrentHardware mixin has no methods.

+ +

Specifications

+ + + + + + + + + + + + + + + + +
SpecificationStatusComment
{{SpecName('HTML WHATWG', '#navigatorconcurrenthardware', 'NavigatorConcurrentHardware')}}{{Spec2('HTML WHATWG')}}Initial definition.
+ +

Browser compatibility

+ + + +

{{Compat("api.NavigatorConcurrentHardware")}}

+ +

See also

+ + -- cgit v1.2.3-54-g00ecf