diff --git a/src/yggdrasil/dht.go b/src/yggdrasil/dht.go index 3d341e7..dcd9a93 100644 --- a/src/yggdrasil/dht.go +++ b/src/yggdrasil/dht.go @@ -41,10 +41,11 @@ type dhtInfo struct { nodeID_hidden *NodeID key boxPubKey coords []byte - send time.Time // When we last sent a message - recv time.Time // When we last received a message - pings int // Decide when to drop - throttle uint8 // Number of seconds to wait before pinging a node to bootstrap buckets, gradually increases up to 1 minute + send time.Time // When we last sent a message + recv time.Time // When we last received a message + pings int // Decide when to drop + throttle time.Duration // Time to wait before pinging a node to bootstrap buckets, increases exponentially from 1 second to 1 minute + bootstrapSend time.Time // The time checked/updated as part of throttle checks } // Returns the *NodeID associated with dhtInfo.key, calculating it on the fly the first time or from a cache all subsequent times. @@ -141,12 +142,14 @@ func (t *dht) handleRes(res *dhtRes) { if !isIn { return } + now := time.Now() rinfo := dhtInfo{ - key: res.Key, - coords: res.Coords, - send: time.Now(), // Technically wrong but should be OK... - recv: time.Now(), - throttle: 1, + key: res.Key, + coords: res.Coords, + send: now, // Technically wrong but should be OK... + recv: now, + throttle: time.Second, + bootstrapSend: now, } // If they're already in the table, then keep the correct send time bidx, isOK := t.getBucketIndex(rinfo.getNodeID()) @@ -157,13 +160,15 @@ func (t *dht) handleRes(res *dhtRes) { for _, oldinfo := range b.peers { if oldinfo.key == rinfo.key { rinfo.send = oldinfo.send - rinfo.throttle += oldinfo.throttle + rinfo.throttle = oldinfo.throttle + rinfo.bootstrapSend = oldinfo.bootstrapSend } } for _, oldinfo := range b.other { if oldinfo.key == rinfo.key { rinfo.send = oldinfo.send - rinfo.throttle += oldinfo.throttle + rinfo.throttle = oldinfo.throttle + rinfo.bootstrapSend = oldinfo.bootstrapSend } } // Insert into table @@ -266,8 +271,8 @@ func (t *dht) insert(info *dhtInfo, isPeer bool) { // This speeds up bootstrapping info.recv = info.recv.Add(-time.Hour) } - if isPeer || info.throttle > 60 { - info.throttle = 60 + if isPeer || info.throttle > time.Minute { + info.throttle = time.Minute } // First drop any existing entry from the bucket b.drop(&info.key) @@ -512,20 +517,39 @@ func (t *dht) doMaintenance() { } } if oldest != nil && time.Since(oldest.recv) > time.Minute { + // Ping the oldest node in the DHT, but don't ping nodes that have been checked within the last minute t.addToMill(oldest, nil) - } // if the DHT isn't empty + } // Refresh buckets if t.offset > last { t.offset = 0 } target := t.getTarget(t.offset) - for _, info := range t.lookup(target, true) { - if time.Since(info.recv) > time.Duration(info.throttle)*time.Second { - t.addToMill(info, target) - t.offset++ - break + func() { + closer := t.lookup(target, false) + for _, info := range closer { + // Throttled ping of a node that's closer to the destination + if time.Since(info.recv) > info.throttle { + t.addToMill(info, target) + t.offset++ + info.bootstrapSend = time.Now() + info.throttle *= 2 + if info.throttle > time.Minute { + info.throttle = time.Minute + } + return + } } - } + if len(closer) == 0 { + // If we don't know of anyone closer at all, then there's a hole in our dht + // Ping the closest node we know and ignore the throttle, to try to fill it + for _, info := range t.lookup(target, true) { + t.addToMill(info, target) + t.offset++ + return + } + } + }() //t.offset++ } for len(t.rumorMill) > 0 {