Always send cancels even if peer has no interest (#829)

* Always send cancels even if peer has no interest
* increase max send delay

Author: gammazero

CHANGELOG.md

@@ -22,6 +22,8 @@ The following emojis are used to highlight certain changes:
 
 ### Fixed
 
+- Fix memory leak due to not cleaning up wantlists [#829](https://github.com/ipfs/boxo/pull/829)
+
 ### Security
 
 

bitswap/client/internal/messagequeue/messagequeue.go

@@ -44,7 +44,7 @@ const (
 	sendTimeout = 30 * time.Second
 
 	defaultPerPeerDelay = time.Millisecond / 8
-	maxSendMessageDelay = time.Second
+	maxSendMessageDelay = 2 * time.Second
 	minSendMessageDelay = 20 * time.Millisecond
 )
 

bitswap/client/internal/sessionmanager/sessionmanager.go

@@ -157,6 +157,11 @@ func (sm *SessionManager) GetNextSessionID() uint64 {
 // their contents. If the caller needs to preserve a copy of the lists it
 // should make a copy before calling ReceiveFrom.
 func (sm *SessionManager) ReceiveFrom(ctx context.Context, p peer.ID, blks []cid.Cid, haves []cid.Cid, dontHaves []cid.Cid) {
+	// Send CANCEL to all peers with want-have / want-block. This needs to be
+	// done before filtering out CIDs that peers are no longer interested in,
+	// to ensure they are removed from PeerManager and PeerQueue want lists.
+	sm.peerManager.SendCancels(ctx, blks)
+
 	// Keep only the keys that at least one session wants
 	keys := sm.sessionInterestManager.FilterInterests(blks, haves, dontHaves)
 	blks = keys[0]
@@ -179,9 +184,6 @@ func (sm *SessionManager) ReceiveFrom(ctx context.Context, p peer.ID, blks []cid
 			sess.ReceiveFrom(p, blks, haves, dontHaves)
 		}
 	}
-
-	// Send CANCEL to all peers with want-have / want-block
-	sm.peerManager.SendCancels(ctx, blks)
 }
 
 // CancelSessionWants is called when a session cancels wants because a call to