Can I sequence the files I download? is quite a common question. This entry will try to anwser the question and possibilities.

Why is this "feature" not implemented in Transmission?

Because it makes the overall swarm's health worse.

But I want to sequence the files I download, how do I do it ?

There're two methodes basicly, one DIY that requires a bit of code changing and the "user frendly" version.

1) DIY code changing approach:
Tweak compareRefillPiece() in libtransmission/peer-mgr.c

Repleace:

/* otherwise go with our random seed */
return tr_compareUint16( a->random, b->random );

With:

/* otherwise download the pieces in order */
return tr_compareUint16( a->piece, b->piece );

2) "User-frendly" approach:
In the file inspector, change the priorities "by hand".