Priority questions

[tsoernes]

I have a couple of questions:

1:
Say file A has a readStream to it and file B is selected. If the peers offer enough bandwidth to download A to fully utilize your own download bandwidth, will file B not start downloading until A is finished? E.g. If your connection is 1000kb/s, and the first and second pieces are selected with highest and lowest priority respectively, but the uploaders for the first piece can only supply 700kb/s while the uploaders for the second piece can supply infinite bandwidth, will the second piece download at 300 kb/s or not at all?

2:
Is there a way to directly set priority to files? E.g. give A priority 1 (highest), B priority 2, C priority 3 and so forth. I guess you could loop through torrent.files, calculate the byte offset and do torrent.select() with priority.

3:
In torrent.select(start, end, [priority], [notify]), is priority 1 highest, 2 second highest and so forth? What priority does file.select() and file.createReadStream() have?

4:
If you do A.select() then B.select(), does A have a higher priority than B, or vice versa, or equal?

Bonus question:

5:
Do most video players use HTTP range requests when playing a video over HTTP? The seek/play position determines the byte start, but what determines the byte range? Is it the buffer size set in the video player?

Thanks

[tsoernes]

2, 3 and 4:
Priority can be any number. Higher number is higher priority. file.select() defaults to priority 0, but as far as I can tell it's actually possible to pass a priority with the method, e.g. file.select(2). file.createReadStream has priority 1.

@feross

I don't know which pieces are prioritized if they are given the same priority. Is it sequential, e.g. lower piece number has a higher priority, or rarest first, or is it not defined at all?

[feross]

Lots of good questions in here. Honestly, it's been so long since I've looked at this code that I'm not sure how it works anymore. Also, I see that you asked this in 2016, so you've probably moved on by now haha 😂

I'm planning to rewrite some of this in the near future, so I'll figure it out then.