From f0894cf8c323a25053e1f5e82be3ea5d88c2aacb Mon Sep 17 00:00:00 2001 From: Paul Jakma Date: Sun, 27 Aug 2006 06:40:04 +0000 Subject: [ospfd] draft-ogier-ospf-dbex-opt DB-exchange optimisation 2006-08-03 Paul Jakma * ospf_packet.c: (ospf_make_db_desc) Implement draft-ogier-ospf-dbex-opt DB-exchange optimisation. --- ospfd/ChangeLog | 1 + ospfd/ospf_packet.c | 48 ++++++++++++++++++++++++++++++++++-------------- 2 files changed, 35 insertions(+), 14 deletions(-) (limited to 'ospfd') diff --git a/ospfd/ChangeLog b/ospfd/ChangeLog index 193f0de5..05f96ace 100644 --- a/ospfd/ChangeLog +++ b/ospfd/ChangeLog @@ -15,6 +15,7 @@ before deciding whether both sides are done, avoids a needless round of empty DD packet exchanges at the end of Exchange, hence speeding up ExchangeDone. + Implement draft-ogier-ospf-dbex-opt DB-exchange optimisation. (ospf_db_desc) use UNSET_FLAG macro. 2006-07-27 Andrew J. Schorr diff --git a/ospfd/ospf_packet.c b/ospfd/ospf_packet.c index 74caaa77..6449e63a 100644 --- a/ospfd/ospf_packet.c +++ b/ospfd/ospf_packet.c @@ -1035,20 +1035,40 @@ ospf_db_desc_proc (struct stream *s, struct ospf_interface *oi, /* Lookup received LSA, then add LS request list. */ find = ospf_lsa_lookup_by_header (oi->area, lsah); - if (!find || ospf_lsa_more_recent (find, new) < 0) - { - ospf_ls_request_add (nbr, new); - ospf_lsa_discard (new); - } - else - { - /* Received LSA is not recent. */ - if (IS_DEBUG_OSPF_EVENT) - zlog_debug ("Packet [DD:RECV]: LSA received Type %d, " - "ID %s is not recent.", lsah->type, inet_ntoa (lsah->id)); - ospf_lsa_discard (new); - continue; - } + + /* ospf_lsa_more_recent is fine with NULL pointers */ + switch (ospf_lsa_more_recent (find, new)) + { + case -1: + /* Neighbour has a more recent LSA, we must request it */ + ospf_ls_request_add (nbr, new); + case 0: + /* If we have a copy of this LSA, it's either less recent + * and we're requesting it from neighbour (the case above), or + * it's as recent and we both have same copy (this case). + * + * In neither of these two cases is there any point in + * describing our copy of the LSA to the neighbour in a + * DB-Summary packet, if we're still intending to do so. + * + * See: draft-ogier-ospf-dbex-opt-00.txt, describing the + * backward compatible optimisation to OSPF DB Exchange / + * DB Description process implemented here. + */ + if (find) + ospf_lsdb_delete (&nbr->db_sum, find); + ospf_lsa_discard (new); + break; + default: + /* We have the more recent copy, nothing specific to do: + * - no need to request neighbours stale copy + * - must leave DB summary list copy alone + */ + if (IS_DEBUG_OSPF_EVENT) + zlog_debug ("Packet [DD:RECV]: LSA received Type %d, " + "ID %s is not recent.", lsah->type, inet_ntoa (lsah->id)); + ospf_lsa_discard (new); + } } /* Master */ -- cgit v1.2.1