Thread (40 messages) 40 messages, 3 authors, 2009-03-02
STALE6326d

[PATCH net-next 02/17] tcp: don't backtrack to sacked skbs

From: Ilpo Järvinen <hidden>
Date: 2009-02-28 14:44:45
Subsystem: networking [general], networking [tcp], the rest · Maintainers: "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds

From: Ilpo Järvinen <redacted>

Backtracking to sacked skbs is a horrible performance killer
since the hint cannot be advanced successfully past them...
...And it's totally unnecessary too.

In theory this is 2.6.27..28 regression but I doubt anybody
can make .28 to have worse performance because of other TCP
improvements.

Signed-off-by: Ilpo Järvinen <redacted>
---
 net/ipv4/tcp_output.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index f6f61b3..2471cd4 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2065,7 +2065,7 @@ begin_fwd:
 			goto begin_fwd;
 
 		} else if (!(sacked & TCPCB_LOST)) {
-			if (hole == NULL && !(sacked & TCPCB_SACKED_RETRANS))
+			if (hole == NULL && !(sacked & (TCPCB_SACKED_RETRANS|TCPCB_SACKED_ACKED)))
 				hole = skb;
 			continue;
 
-- 
1.5.6.5
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help