table: avoid cloning path for withdraw

when a peer having lots of routes goes down, the cloning paths consume
too much memory.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

1 files changed, 8 insertions, 1 deletions

diff --git a/table/destination.go b/table/destination.go
index 50d779df..2216abca 100644
--- a/table/destination.go
+++ b/table/destination.go
@@ -234,7 +234,7 @@ func (dd *Destination) validatePath(path *Path) {
 //
 // Modifies destination's state related to stored paths. Removes withdrawn
 // paths from known paths. Also, adds new paths to known paths.
-func (dest *Destination) Calculate(ids []string) (map[string]*Path, map[string]*Path, []*Path) {
+func (dest *Destination) Calculate(ids []string, peerDown bool) (map[string]*Path, map[string]*Path, []*Path) {
 	bestList := make(map[string]*Path, len(ids))
 	oldList := make(map[string]*Path, len(ids))
 	oldKnownPathList := dest.knownPathList
@@ -272,6 +272,13 @@ func (dest *Destination) Calculate(ids []string) (map[string]*Path, map[string]*
 			if old == nil {
 				return nil, nil
 			}
+			if peerDown {
+				// withdraws were generated by peer
+				// down so paths are not in knowpath
+				// or adjin.
+				old.IsWithdraw = true
+				return old, old
+			}
 			return old.Clone(true), old
 		}
 		return best, old