[LARTC] police rate doesn't work ?

[Vitale Alessandro]

I would like to test police in ingress.
I use kernel 2.4.20.
I use this configuration:

iptables -t mangle -A PREROUTING -i eth0 -s 10.31.12.2 -d 10.31.11.2 -p udp --dport 1001 -j MARK --set-mark 1
iptables -t mangle -A PREROUTING -i eth0 -s 10.31.12.2 -d 10.31.11.2 -p udp --dport 1002 -j MARK --set-mark 2
iptables -t mangle -A PREROUTING -i eth0 -s 10.31.12.2 -d 10.31.11.2 -p udp --dport 1003 -j MARK --set-mark 3
iptables -t mangle -A PREROUTING -i eth0 -s 10.31.12.2 -d 10.31.11.2 -p udp --dport 1004 -j MARK --set-mark 4

tc qdisc add dev eth0 handle ffff: ingress
tc filter add dev eth0 parent ffff: protocol ip prio 1 handle 1 fw police rate 2500000 burst 90k drop
tc filter add dev eth0 parent ffff: protocol ip prio 1 handle 2 fw police rate 1500000 burst 90k drop
tc filter add dev eth0 parent ffff: protocol ip prio 1 handle 3 fw police rate 1000000 burst 90k drop


I generate traffic with smartbits and i made this test:
1)len packet layer2 64 byte, packets per second 5500 = 2810000 bit per second
2)len packet layer2 1000 byte, packets per second 350 = 2800000 bit per second

The 2 test is good i receive a trafiic with 2500000 rate limit !
The problem is with 1 test because i received full band 2810000 without any limit!

Is there any problem with police rate? It doesn't work  with small packets?
I've to set some other usefull parameter?

Please help me !