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SharedArrayBuffer对象

SharedArrayBuffer内部包含一块Native内存,其JS对象壳被分配在虚拟机本地堆(LocalHeap)。支持跨并发实例间共享Native内存,但是对共享Native内存的访问及修改需要采用Atomics类,防止数据竞争。SharedArrayBuffer可用于多个并发实例间的状态或数据共享。通信过程如下图所示:

使用示例

使用TaskPool传递Int32Array对象,实现如下:

import { taskpool } from '@kit.ArkTS';

@Concurrent
function transferAtomics(arg1: Int32Array) {
console.info('wait begin::');
// 使用Atomics进行操作
let res = Atomics.wait(arg1, 0, 0, 3000);
return res;
}

@Entry
@Component
struct sharedArrayBuffer {
@State message: string = 'Hello World';

build() {
RelativeContainer() {
Text(this.message)
.id('HelloWorld')
.fontSize(50)
.fontWeight(FontWeight.Bold)
.alignRules({
center: { anchor: '__container__', align: VerticalAlign.Center },
middle: { anchor: '__container__', align: HorizontalAlign.Center }
})
.onClick(() => {
// 定义可共享对象
let sab: SharedArrayBuffer = new SharedArrayBuffer(20);
let int32 = new Int32Array(sab);
let task: taskpool.Task = new taskpool.Task(transferAtomics, int32);
taskpool.execute(task).then((res) => {
console.info('this res is: ' + res);
});
setTimeout(() => {
Atomics.notify(int32, 0, 1);
}, 1000);
this.message = 'success';
})
}
.height('100%')
.width('100%')
}
}