[LARTC] tc qdisc ingress problem ?

[LARTC] tc qdisc ingress problem ?

[Laurent Haond]

Hi, all

I've got problems with tc qdisc ingress.
I'm using vanillia kernel 2.6.14.4 patched with
http://www.ssi.bg/~ja/routes-2.6.14-12.diff, and iproute2-2.6.14-051107.

i am using ingress to limit incoming traffic :
(DEV is eth1 /  DOWNLINK is 7700)

# attach ingress policer:
tc qdisc add dev $DEV handle ffff: ingress

# filter *everything* to it (0.0.0.0/0), drop everything that's
# coming in too fast:
tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip src \lm
   0.0.0.0/0 police rate ${DOWNLINK}kbit burst 10k drop flowid :1

This does limit traffic but to ~32KB/s !!

#tc -s qdisc show dev eth1
[...]
qdisc ingress ffff: ----------------
 Sent 37001411 bytes 51120 pkt (dropped 3422, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0

It's is normal to have dropped packets without overlimits ??

Could it be related to CPU performance (overload), i'm using a wrap2
board (geode sc1100 at 266Mhz) ?
Running top during a big download, it appears that cpu is 95% idle...

Thanks

Laurent Haond

_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc

Re: [LARTC] tc qdisc ingress problem ?

[Laurent Haond]

Laurent Haond a écrit :

>Hi, all
>
>I've got problems with tc qdisc ingress.
>I'm using vanillia kernel 2.6.14.4 patched with
>http://www.ssi.bg/~ja/routes-2.6.14-12.diff, and iproute2-2.6.14-051107.
>
>i am using ingress to limit incoming traffic :
>(DEV is eth1 /  DOWNLINK is 7700)
>
># attach ingress policer:
>tc qdisc add dev $DEV handle ffff: ingress
>
># filter *everything* to it (0.0.0.0/0), drop everything that's
># coming in too fast:
>tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip src \lm
>   0.0.0.0/0 police rate ${DOWNLINK}kbit burst 10k drop flowid :1
>
>This does limit traffic but to ~32KB/s !!
>
>#tc -s qdisc show dev eth1
>[...]
>qdisc ingress ffff: ----------------
> Sent 37001411 bytes 51120 pkt (dropped 3422, overlimits 0 requeues 0)
> rate 0bit 0pps backlog 0b 0p requeues 0
>
>It's is normal to have dropped packets without overlimits ??
>
>Could it be related to CPU performance (overload), i'm using a wrap2
>board (geode sc1100 at 266Mhz) ?
>Running top during a big download, it appears that cpu is 95% idle...
>
>Thanks
>
>Laurent Haond
>
>_______________________________________________
>LARTC mailing list
>LARTC@mailman.ds9a.nl
>http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartcen
>  
>
Finally,

I've found the solution, on this hardware it seems that NET_SCH clock
cannot rely on CPU clock,
I recompiled a kernel with :
CONFIG_NET_SCH_CLK_GETTIMEOFDAY=y
instead of
CONFIG_NET_SCH_CLK_CPU=y
and now everything seems to be OK.

Laurent


_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc