diff options
| author | Henning Brauer <henning@cvs.openbsd.org> | 2009-08-12 15:58:21 +0000 |
|---|---|---|
| committer | Henning Brauer <henning@cvs.openbsd.org> | 2009-08-12 15:58:21 +0000 |
| commit | b6c1a50d5d1b9d2bb2a9081166fcae595ab222e6 (patch) | |
| tree | 7de3e8f48ba303d95a806cf2e21bc760f17e5d1d /sys/net | |
| parent | a7e5a1a9e591b89d53a226dd10d844bb13065a57 (diff) | |
dlg deferred calling interfaces' if_start routine so we call them less,
which does pay out, performance wise. one of the conditions to call the
interfaces' if_start routine immediately was "send queue is full".
on a very busy (hammered) machine this will itroduce too much latency
since we spend almost all cpu time in interrupt handlers and softnet,
so the softint actually doing the if_start gets called to seldom and
the queue full check is what triggers the actual transmit.
change the logic to call if's if_start routing immediately when there are
at least 8 packets (or in case if maxlen being smaller than 8, maxlen)
8 chose because it shows best performance in my test setup here.
ok dlg
Diffstat (limited to 'sys/net')
| -rw-r--r-- | sys/net/if.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/sys/net/if.c b/sys/net/if.c index df140d42cb2..5adb852e14c 100644 --- a/sys/net/if.c +++ b/sys/net/if.c @@ -1,4 +1,4 @@ -/* $OpenBSD: if.c,v 1.198 2009/08/10 11:22:10 deraadt Exp $ */ +/* $OpenBSD: if.c,v 1.199 2009/08/12 15:58:20 henning Exp $ */ /* $NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $ */ /* @@ -471,7 +471,8 @@ if_attach_common(struct ifnet *ifp) void if_start(struct ifnet *ifp) { - if (IF_QFULL(&ifp->if_snd) && !ISSET(ifp->if_flags, IFF_OACTIVE)) { + if (ifp->if_snd.ifq_len >= min(8, ifp->if_snd.ifq_maxlen) && + !ISSET(ifp->if_flags, IFF_OACTIVE)) { if (ISSET(ifp->if_xflags, IFXF_TXREADY)) { TAILQ_REMOVE(&iftxlist, ifp, if_txlist); CLR(ifp->if_xflags, IFXF_TXREADY); |