server: reduce number of path.Clone() call to reduce memory footprint

the result of memory profile (500 route-server-clients each of them
advertises 100 routes)

before:
(pprof) top5
3913.02MB of 3978.69MB total (98.35%)
Dropped 148 nodes (cum <= 19.89MB)
Showing top 10 nodes out of 11 (cum >= 21MB)
flat       flat%   sum%        cum   cum%
2970.30MB 74.66% 74.66%  2975.80MB 74.79% github.com/osrg/gobgp/server.filterpath
810.09MB  20.36% 95.02%   810.59MB 20.37% github.com/osrg/gobgp/table.(*AdjRib).Update
115.60MB   2.91% 97.92%   119.10MB  2.99% github.com/osrg/gobgp/table.createUpdateMsgFromPath
10MB       0.25% 98.17%  1878.02MB 47.20% github.com/osrg/gobgp/server.(*BgpServer).propagateUpdate
4.50MB     0.11% 98.29%   144.60MB  3.63% github.com/osrg/gobgp/table.CreateUpdateMsgFromPaths

after:
(pprof) top5
1259.49MB of 1284.27MB total (98.07%)
Dropped 175 nodes (cum <= 6.42MB)
Showing top 10 nodes out of 26 (cum >= 36.51MB)
flat     flat%  sum%        cum   cum%
975.81MB 75.98% 75.98%   976.31MB 76.02% github.com/osrg/gobgp/table.(*AdjRib).Update
198.67MB 15.47% 91.45%   208.17MB 16.21% github.com/osrg/gobgp/table.createUpdateMsgFromPath
22MB      1.71% 93.16%       22MB  1.71% github.com/osrg/gobgp/packet.(*IPAddrPrefix).Serialize
20MB      1.56% 94.72%   707.19MB 55.07% github.com/osrg/gobgp/server.(*BgpServer).propagateUpdate
13.50MB   1.05% 95.77%    13.50MB  1.05% github.com/osrg/gobgp/table.NewPath

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>

2 files changed, 14 insertions, 6 deletions

diff --git a/server/peer.go b/server/peer.go
index c4e09617..ef08a4d8 100644
--- a/server/peer.go
+++ b/server/peer.go
@@ -105,13 +105,17 @@ func (peer *Peer) getAccepted(rfList []bgp.RouteFamily) []*table.Path {
 func (peer *Peer) getBestFromLocal(rfList []bgp.RouteFamily) ([]*table.Path, []*table.Path) {
 	pathList := []*table.Path{}
 	filtered := []*table.Path{}
+	options := &table.PolicyOptions{
+		Neighbor: peer.fsm.peerInfo.Address,
+	}
 	for _, path := range peer.localRib.GetBestPathList(peer.TableID(), rfList) {
-		p := peer.policy.ApplyPolicy(peer.TableID(), table.POLICY_DIRECTION_EXPORT, filterpath(peer, path), nil)
+		p := peer.policy.ApplyPolicy(peer.TableID(), table.POLICY_DIRECTION_EXPORT, filterpath(peer, path), options)
 		if p == nil {
 			filtered = append(filtered, path)
 			continue
 		}
 		if !peer.isRouteServerClient() {
+			p = p.Clone(p.IsWithdraw)
 			p.UpdatePathAttrs(&peer.gConf, &peer.conf)
 		}
 		pathList = append(pathList, p)
diff --git a/server/server.go b/server/server.go
index 7c18f088..bdf8988a 100644
--- a/server/server.go
+++ b/server/server.go
@@ -556,7 +556,7 @@ func filterpath(peer *Peer, path *table.Path) *table.Path {
 	if !peer.isRouteServerClient() && isASLoop(peer, path) {
 		return nil
 	}
-	return path.Clone(peer.fsm.peerInfo.Address, path.IsWithdraw)
+	return path
 }
 
 func (server *BgpServer) dropPeerAllRoutes(peer *Peer) []*SenderMsg {
@@ -765,6 +765,7 @@ func (server *BgpServer) propagateUpdate(peer *Peer, pathList []*table.Path) ([]
 	msgs := make([]*SenderMsg, 0)
 	rib := server.globalRib
 	var alteredPathList []*table.Path
+	options := &table.PolicyOptions{}
 	if peer != nil && peer.isRouteServerClient() {
 		for _, path := range pathList {
 			path.Filter(peer.ID(), table.POLICY_DIRECTION_IMPORT)
@@ -783,8 +784,9 @@ func (server *BgpServer) propagateUpdate(peer *Peer, pathList []*table.Path) ([]
 				continue
 			}
 			sendPathList := make([]*table.Path, 0, len(dsts))
+			options.Neighbor = targetPeer.fsm.peerInfo.Address
 			for _, dst := range dsts {
-				path := server.policy.ApplyPolicy(targetPeer.TableID(), table.POLICY_DIRECTION_EXPORT, filterpath(targetPeer, dst.NewFeed(targetPeer.TableID())), nil)
+				path := server.policy.ApplyPolicy(targetPeer.TableID(), table.POLICY_DIRECTION_EXPORT, filterpath(targetPeer, dst.NewFeed(targetPeer.TableID())), options)
 				if path != nil {
 					sendPathList = append(sendPathList, path)
 				}
@@ -818,9 +820,11 @@ func (server *BgpServer) propagateUpdate(peer *Peer, pathList []*table.Path) ([]
 			}
 			pathList := make([]*table.Path, len(sendPathList))
 			copy(pathList, sendPathList)
+			options.Neighbor = targetPeer.fsm.peerInfo.Address
 			for idx, path := range pathList {
-				path = server.policy.ApplyPolicy(table.GLOBAL_RIB_NAME, table.POLICY_DIRECTION_EXPORT, filterpath(targetPeer, path), nil)
+				path = server.policy.ApplyPolicy(table.GLOBAL_RIB_NAME, table.POLICY_DIRECTION_EXPORT, filterpath(targetPeer, path), options)
 				if path != nil {
+					path = path.Clone(path.IsWithdraw)
 					path.UpdatePathAttrs(&server.bgpConfig.Global, &targetPeer.conf)
 				}
 				pathList[idx] = path
@@ -1276,7 +1280,7 @@ func (server *BgpServer) handleModPathRequest(grpcReq *GrpcRequest) []*table.Pat
 					return nil
 				}()
 				if path != nil {
-					paths = append(paths, path.Clone(path.Owner, true))
+					paths = append(paths, path.Clone(true))
 				} else {
 					err = fmt.Errorf("Can't find a specified path")
 				}
@@ -1818,7 +1822,7 @@ func (server *BgpServer) handleGrpc(grpcReq *GrpcRequest) []*SenderMsg {
 			pathList := []*table.Path{}
 			for _, path := range peer.adjRibIn.PathList([]bgp.RouteFamily{grpcReq.RouteFamily}, false) {
 				if path = server.policy.ApplyPolicy(peer.ID(), table.POLICY_DIRECTION_IN, path, nil); path != nil {
-					pathList = append(pathList, path.Clone(net.ParseIP(peer.conf.Config.NeighborAddress), false))
+					pathList = append(pathList, path.Clone(false))
 				}
 			}
 			m, _ := server.propagateUpdate(peer, pathList)