les: implement request distributor, fix blocking issues (#3660)

* les: implement request distributor, fix blocking issues
* core: moved header validation before chain mutex lock

1 files changed, 0 insertions, 76 deletions

diff --git a/les/serverpool.go b/les/serverpool.go
index 55d481dbf..64fe991c6 100644
--- a/les/serverpool.go
+++ b/les/serverpool.go
@@ -268,82 +268,6 @@ func (pool *serverPool) adjustResponseTime(entry *poolEntry, time time.Duration,
 	}
 }
 
-type selectPeerItem struct {
-	peer   *peer
-	weight int64
-	wait   time.Duration
-}
-
-func (sp selectPeerItem) Weight() int64 {
-	return sp.weight
-}
-
-// selectPeer selects a suitable peer for a request, also returning a necessary waiting time to perform the request
-// and a "locked" flag meaning that the request has been assigned to the given peer and its execution is guaranteed
-// after the given waiting time. If locked flag is false, selectPeer should be called again after the waiting time.
-func (pool *serverPool) selectPeer(reqID uint64, canSend func(*peer) (bool, time.Duration)) (*peer, time.Duration, bool) {
-	pool.lock.Lock()
-	type selectPeer struct {
-		peer         *peer
-		rstat, tstat float64
-	}
-	var list []selectPeer
-	sel := newWeightedRandomSelect()
-	for _, entry := range pool.entries {
-		if entry.state == psRegistered {
-			if !entry.peer.fcServer.IsAssigned() {
-				list = append(list, selectPeer{entry.peer, entry.responseStats.recentAvg(), entry.timeoutStats.recentAvg()})
-			}
-		}
-	}
-	pool.lock.Unlock()
-
-	for _, sp := range list {
-		ok, wait := canSend(sp.peer)
-		if ok {
-			w := int64(1000000000 * (peerSelectMinWeight + math.Exp(-(sp.rstat+float64(wait))/float64(responseScoreTC))*math.Pow((1-sp.tstat), timeoutPow)))
-			sel.update(selectPeerItem{peer: sp.peer, weight: w, wait: wait})
-		}
-	}
-	choice := sel.choose()
-	if choice == nil {
-		return nil, 0, false
-	}
-	peer, wait := choice.(selectPeerItem).peer, choice.(selectPeerItem).wait
-	locked := false
-	if wait < time.Millisecond*100 {
-		if peer.fcServer.AssignRequest(reqID) {
-			ok, w := canSend(peer)
-			wait = time.Duration(w)
-			if ok && wait < time.Millisecond*100 {
-				locked = true
-			} else {
-				peer.fcServer.DeassignRequest(reqID)
-				wait = time.Millisecond * 100
-			}
-		}
-	} else {
-		wait = time.Millisecond * 100
-	}
-	return peer, wait, locked
-}
-
-// selectPeer selects a suitable peer for a request, waiting until an assignment to
-// the request is guaranteed or the process is aborted.
-func (pool *serverPool) selectPeerWait(reqID uint64, canSend func(*peer) (bool, time.Duration), abort <-chan struct{}) *peer {
-	for {
-		peer, wait, locked := pool.selectPeer(reqID, canSend)
-		if locked {
-			return peer
-		}
-		select {
-		case <-abort:
-			return nil
-		case <-time.After(wait):
-		}
-	}
-}
-
 // eventLoop handles pool events and mutex locking for all internal functions
 func (pool *serverPool) eventLoop() {
 	lookupCnt := 0