diff --git a/pstoremem/addr_book.go b/pstoremem/addr_book.go
index 7aa0c3f..cd7a920 100644
--- a/pstoremem/addr_book.go
+++ b/pstoremem/addr_book.go
@@ -112,6 +112,7 @@ func (mab *memoryAddrBook) gc() {
 				delete(s.addrs, p)
 			}
 		}
+		atomic.StoreUint32(&s.size, uint32(len(s.addrs)))
 		s.lk.Unlock()
 	}