Low performance when read large file with cordova-plugin-file

am creating a hybrid app with Angular 7, Ionic 4 and Cordova.

I need to read a large file (> 1GB) located on Android file system but i am facing a performance issue. With the current implementation i have a speed about **2.5 MB/sec**.

Is it an issue with the plugin itself or the implementation ?

I tried to modify BLOB_SIZE but the maximum speed i obtained was 2.5 MB/s.

```typescript
const BLOB_SIZE = 1024*1024;

usbRead(fileEntry: FileEntry) {
fileEntry.file((file) => {
const reader = new FileReader();

reader.onload = () => {
const buffer = new Uint8Array(reader.result as ArrayBuffer);
readCounter += buffer.byteLength;
console.log(textDecoder.decode(buffer));
offset += BLOB_SIZE;
if (offset >= file.size) {
console.log('end');
return;
}
const slice = file.slice(offset, offset + BLOB_SIZE);
reader.readAsArrayBuffer(slice);
};

reader.readAsArrayBuffer(file.slice(0, BLOB_SIZE));
});
});
}
```
I tested on Xiaomi Redmi Note 7 with Android 9

My package.json has the following plugin version :
`@ionic-native/file": "^5.12.0"`

- [x] I searched for existing GitHub issues
- [x] I updated all Cordova tooling to most recent version
- [x] I included all the necessary information above

Reproduce the reported read loop on the Xiaomi Redmi Note 7/Android 9 using the supplied TypeScript code and compare results with different BLOB_SIZE values. Trace the cordova-plugin-file read path and the FileReader slicing loop to determine whether the bottleneck is in the plugin or the implementation; done means the cause and any supported limitation are established.

Written by the indexing model from the issue text.