Downloading many files keeps increasing memory usage and can eventually crash application

[cal-g]

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Issue Info

Info	Value
Platform Name	flutter
Platform Version	Flutter 3.0.5
Dio Version	4.0.6
Android Studio / Xcode Version	Xcode 13.4
Repro rate	all the time (100%)
Repro with our demo prj	Yes, it also happens with download example.
Demo project link	Demo gist

Issue Description and Steps

When using the dio.download api for downloading many small files the memory keeps increasing. The memory does reduce a bit , about 10%, after a while but stays high for the most part. The memory can quickly reach to very high levels if downloading a lot of images (200+) and the application will eventually crash for low RAM devices such as an iPhone8 which has only 2GB RAM.

Dart Observatory and Memory Tab (Flutter DevTools) screenshots :

At the beginning of app start (Before downloading file) :

After tapping the button 3 times (60 files downloaded):

[liqping]

This issue maybe caused by Dart http https://github.com/flutter/flutter/issues/108513