Try the following: tc qdisc del root dev eth0 tc qdisc add dev eth0 root handle 1: prio tc filter add dev eth0 parent 1:0 protocol all u32 match u32 0x00000000 0x00000000 at 0 flowid 1:3 tc filter add dev eth0 parent 1:0 protocol all u32 match u32 0x00E00000 0x00E00000 at 0 flowid 1:1 ping -Q 255 192.168.1.1 tc -s class ls dev eth0 The first command deletes the qdisc on eth0 The second creates the prio qdisc the third line is a filter that takes all that did not match the fourth line filter rule to 1:3 the fourth line takes the frames matching 0x00E00000 (with mask 0x00E00000) at position 0 of ip packet to class 1:1 You can check with a ping -Q and the dump of the classes. Le mardi 17 novembre 2009 à 14:14 -0800, David L a écrit : > Hi, > > I need to prioritize data sent on a socket over a ppp link > so it is transmitted before some other data sharing that link. > I googled around for a few days and I thought I understood > how I might go about doing this, but my attempts have > failed. > > I thought the default qdisc (pfifo_fast) would prioritize data > flagged as "lowdelay" by putting it in a different band that has > preferential queuing priority over data in other bands. I > attempted to configure the socket like this: > > int lowdelay = IPTOS_LOWDELAY; > return setsockopt(servFd_, IPPROTO_IP, IP_TOS, > (void *)&lowdelay, sizeof(lowdelay)); > > > And I verified that the data had TOS=0x10 using tcpdump: > > tcpdump -v -v -i ppp0 > 13:47:00.259910 IP (tos 0x10, ttl 64, id 26932, offset 0, flags [DF], > proto TCP (6), length 67) > 10.10.12.2.irisa > 10.10.12.1.41152: Flags [P.], cksum 0x178a > (correct), seq 480:495, ack 1, win 91, options [nop,nop,TS val > 10108331 ecr 683540551], length 15 > ... > > But when I browse a web page through that same ppp link, > the 5Hz data that I'm expecting through the priority socket > has delays of up to a second. This is well over the maximum > delay I expected, which was around MTU/baud rate assuming > one big message was queued just before I send the next 5 > Hz priority message. I tried UDP sockets too in case it > was the low priority ack that was causing the problem, but that > didn't seem to make a difference. > > Any ideas what I'm doing wrong? > > Thanks, > > David > -- > To unsubscribe from this list: send the line "unsubscribe linux-net" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
