prevent corrupt downloads after app and/or system crash #1644
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Problem:
Segments (technically , chunks of in-flight pieces) are marked as finished in the control file (*.aria2) as they are downloaded, though they might not be permanently written, yet, to the storage medium. In the case of app or system crash, and after resuming the download, some segments might have been lost, but the control file marks them as finished.
There is as significant chance for this to happen because of the delay introduced by the in-app disk cache and the OS buffers before the actual physical disk write. By default, auto-save interval is 60 seconds, while, in my case, linux buffer cache had >15s delay and the delay of in-app caches are highly dependent on the download speed because they are flushed once a whole piece completes, which makes it worse for slow network or parallel downloads.
Solution:
Flush data from the caches before saving control file.