[altq 181] Re: hfsc problems

[Kenjiro Cho <kjc@csl.sony.co.jp>]

Prashant,

I suspect the window size of TCP is not big enough.  What window size
do you set to TCP?
You can confirm it by watching the "period" counter in the hfscstat
output.  The "period" counter shows the number of the state transition
from idle to backlogged.  If the "period" counter increases during the
test, the queue does not have packets all the time.

-Kenjiro

Prashant Chandra <prashant+@cs.cmu.edu> wrote:
> I used the following config file:
> 
> aruba:~prashant/cp/darwin/beagle/freebsd-altq> more
> test.conf
> interface de1 bandwidth 9M hfsc   
> class hfsc de1 def_class root pshare 10 default  
> #class hfsc de1 class1 root grate 5M pshare 45
> class hfsc de1 class1 root [sc 0 0 4M]
>         filter de1 class1 192.168.64.1 0
> 192.168.61.1 0 6
> #class hfsc de1 class2 root grate 3M pshare 45
> class hfsc de1 class2 root [sc 0 0 3M]
>         filter de1 class2 192.168.65.1 0 192.168.6.1
> 0 17
> 
> I expected to see at least 4 Mbps for TCP and 3 Mbps
> for UDP.  
> Instead I saw 1.22 Mbps for TCP and 2.9 Mbps for UDP
> at the
> receiver.
> 
> The output of hfscstat is shown below.  
> 
> cur_time:0x11434037d25 4 classes 52 packets in the
> tree
> [ 2] handle:0xc0d28e00 [rt 0K 0ms 3999K][ls 0K 0ms
> 3999K]
>       0.80Mbps [  0.63M:  0.17M] qlen: 2
> period:28347
>   cumul:0xfe6d14 total:0x2ba88b8
>   vt:0x18dcdc088e d:0x1143416ae42 e:0x1143401d77a
> [ 3] handle:0xc0d28c00 [rt 0K 0ms 2999K][ls 0K 0ms
> 2999K]
>       9.19Mbps [  2.69M:  6.50M] qlen:50 period:5209
>   cumul:0x18b08f2 total:0x54ac4ec
>   vt:0x18dcf0df52 d:0x114342c74d6 e:0x1143410abcd
> 
> If I just send UDP or TCP alone, I get 9.32 Mbps
> with TCP and
> 8.95 Mbps with UDP.  The bottlneck link rate is set
> to 9 Mbps in the
> config file.  I am sending UDP at a controlled rate
> of about 10 Mbps.
> 
> Just TCP:
> 
> cur_time:0x1313bad3aae 4 classes 0 packets in the
> tree
> [ 2] handle:0xc0d28e00 [rt 0K 0ms 3999K][ls 0K 0ms
> 3999K]
>       9.84Mbps [  3.25M:  6.59M] qlen: 0
> period:36899
>   cumul:0x146296e total:0x388f40e
>   vt:0x1d03cf607f d:0x1313bc15319 e:0x1313bac7c51
> 
> 
> Just UDP:
> 
> cur_time:0x13943fe104a 4 classes 0 packets in the
> tree
> [ 3] handle:0xc0d28c00 [rt 0K 0ms 2999K][ls 0K 0ms
> 2999K]
>       9.96Mbps [  1.79M:  8.16M] qlen: 0 period:7889
>   cumul:0x1bf5adc total:0x62693ba
>   vt:0x1ce5a2e086 d:0x13944097e55 e:0x13943fa300e
> 
> 
> I feel this is caused by me not doing everything
> right
> in the config file.  I would appreciate if someone
> could
> tell me what I did wrong.
> 
> Thanks in advance.
>   -prashant
> -- 
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