目录

@ohos.app.ability.appMemoryOptimizer (Application Memory Optimizer)

appMemoryOptimizer provides application memory optimization capabilities, including releasing the file page cache of a specified file and releasing the file page cache of a specified module. For example, when an app enters the background or the device memory is tight, calling evictFilePages to release the file page cache of loaded files can reduce the app's own memory usage.

Since: 26.0.0

Modules to Import

import { appMemoryOptimizer } from '@kit.AbilityKit';

appMemoryOptimizer.evictFilePages

evictFilePages(fileNames: Array<string>): Promise<void>

Requests the system to release the file page cache of the specified files. The system determines whether to actually perform the release based on the current memory status, and the release is not guaranteed to succeed. This API uses a promise to return the result.

Since: 26.0.0

Model restriction: This API can be used only in the stage model.

System capability: SystemCapability.Ability.AbilityRuntime.Core

Parameters

Name Type Mandatory Description
fileNames Array<string> Yes Array of file names whose file page cache is to be released. Each file name must end with .so, .hap, or .hsp.

Return value

Type Description
Promise<void> Promise that returns no value.

Error codes

For details about the error codes, see Universal Error Codes and Ability Error Codes.

ID Error Message
16000163 File type error. File name does not end with .so, .hap, or .hsp.

Example

import { appMemoryOptimizer } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  appMemoryOptimizer.evictFilePages(['libentry.so', 'sharedLibrary.hsp'])
    .then(() => {
      console.info('EvictFilePages success.');
    })
    .catch((err: BusinessError) => {
      console.error(`EvictFilePages failed, error code: ${err.code}, error msg: ${err.message}.`);
    });
} catch (error) {
  console.error('EvictFilePages failed, error: ' + JSON.stringify(error));
}

appMemoryOptimizer.evictModuleFilePages

evictModuleFilePages(moduleNames: Array<string>): Promise<void>

Requests the system to release the file page cache of the specified modules. The system determines whether to actually perform the release based on the current memory status, and successful release is not guaranteed. The system reads the memory_optimizer.json configuration file in the corresponding module (path: {module directory}/src/main/resources/rawfile/memory_optimizer.json), obtains the evictFilePages array, and then releases the file page cache based on the file names configured in the array. The file names in the evictFilePages array must end with .so, .hap, or .hsp. This API uses a promise to return the result.

Since: 26.0.0

Model restriction: This API can be used only in the stage model.

System capability: SystemCapability.Ability.AbilityRuntime.Core

Parameters

Name Type Mandatory Description
moduleNames Array<string> Yes Array of module names whose file page cache is to be released.

Return value

Type Description
Promise<void> Promise that returns no value.

Error codes

For details about the error codes, see Universal Error Codes and Ability Error Codes.

ID Error Message
16000163 File type error. File names in the evictFilePages array of the configuration file do not end with .so, .hap, or .hsp.
16000164 Failed to parse configuration file.

Example

Example of the configuration file src/main/resources/rawfile/memory_optimizer.json of the entry module:

{
  "evictFilePages": [
    "libentry.so",
    "sharedLibrary.hsp"
  ]
}

Example

import { appMemoryOptimizer } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  appMemoryOptimizer.evictModuleFilePages(['entry'])
    .then(() => {
      console.info('EvictModuleFilePages success.');
    })
    .catch((err: BusinessError) => {
      console.error(`EvictModuleFilePages failed, error code: ${err.code}, error msg: ${err.message}.`);
    });
} catch (error) {
  console.error('EvictFilePages failed, error: ' + JSON.stringify(error));
}