p2p: reduce buffering on channels (#6609)

Having smaller buffers in each reactor/channel will mean that there will be fewer stale messages.

internal/p2p/pex/reactor.go

@@ -51,8 +51,8 @@ func ChannelDescriptor() conn.ChannelDescriptor {
 		Priority:            1,
 		SendQueueCapacity:   10,
 		RecvMessageCapacity: maxMsgSize,
-
-		MaxSendBytes: 200,
+		RecvBufferCapacity:  32,
+		MaxSendBytes:        200,
 	}
 }
 
@@ -417,6 +417,7 @@ func (r *ReactorV2) sendRequestForPeers() {
 		// no peers are available
 		r.Logger.Debug("no available peers to send request to, waiting...")
 		r.nextRequestTime = time.Now().Add(noAvailablePeersWaitPeriod)
+
 		return
 	}
 	var peerID types.NodeID

internal/p2p/router.go

@@ -19,7 +19,7 @@ import (
 	"github.com/tendermint/tendermint/types"
 )
 
-const queueBufferDefault = 4096
+const queueBufferDefault = 32
 
 // ChannelID is an arbitrary channel ID.
 type ChannelID uint16
@@ -365,10 +365,6 @@ func (r *Router) createQueueFactory() (func(int) queue, error) {
 // wrapper message. The caller may provide a size to make the channel buffered,
 // which internally makes the inbound, outbound, and error channel buffered.
 func (r *Router) OpenChannel(chDesc ChannelDescriptor, messageType proto.Message, size int) (*Channel, error) {
-	if size == 0 {
-		size = queueBufferDefault
-	}
-
 	r.channelMtx.Lock()
 	defer r.channelMtx.Unlock()