From 610f8e01858b330801ea75e5202e5193252638d1 Mon Sep 17 00:00:00 2001
From: Matt Joiner <anacrolix@gmail.com>
Date: Mon, 11 Oct 2021 16:21:26 +1100
Subject: [PATCH] Don't put requests we can't make into the request heap

In particular this should save a lot of overhead if we're choked.
---
 requesting.go | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/requesting.go b/requesting.go
index c5cd459e..737771fe 100644
--- a/requesting.go
+++ b/requesting.go
@@ -180,8 +180,7 @@ func (p *peerRequests) Pop() interface{} {
 func (p *Peer) getDesiredRequestState() (desired requestState) {
 	input := p.t.cl.getRequestStrategyInput()
 	requestHeap := peerRequests{
-		requestIndexes: nil,
-		peer:           p,
+		peer: p,
 	}
 	for _, t := range input.Torrents {
 		if t.InfoHash == p.t.infoHash {
@@ -198,6 +197,15 @@ func (p *Peer) getDesiredRequestState() (desired requestState) {
 			if !p.peerHasPiece(pieceIndex) {
 				return
 			}
+			allowedFast := p.peerAllowedFast.ContainsInt(pieceIndex)
+			if !allowedFast {
+				// We must signal interest to request this piece.
+				desired.Interested = true
+				if p.peerChoking {
+					// We can't request from this piece right now then.
+					return
+				}
+			}
 			rsp.IterPendingChunks.Iter(func(ci request_strategy.ChunkIndex) {
 				requestHeap.requestIndexes = append(
 					requestHeap.requestIndexes,
@@ -208,14 +216,7 @@ func (p *Peer) getDesiredRequestState() (desired requestState) {
 	heap.Init(&requestHeap)
 	for requestHeap.Len() != 0 && desired.Requests.GetCardinality() < uint64(p.nominalMaxRequests()) {
 		requestIndex := heap.Pop(&requestHeap).(RequestIndex)
-		pieceIndex := requestIndex / p.t.chunksPerRegularPiece()
-		allowedFast := p.peerAllowedFast.Contains(pieceIndex)
-		if !allowedFast {
-			desired.Interested = true
-		}
-		if allowedFast || !p.peerChoking {
-			desired.Requests.Add(requestIndex)
-		}
+		desired.Requests.Add(requestIndex)
 	}
 	return
 }
-- 
2.48.1