Subject: Re: [PATCH iproute2] Re: HTB accuracy for high speed

From: Jarek Poplawski <[email-masked]>
Date: Mon, 18 May 2009 21:05:41 +0200

On Mon, May 18, 2009 at 07:56:12PM +0100, Antonio Almeida wrote:
> Precise measurements:
> 
> 800 bytes:
> class htb 1:108 parent 1:10 leaf 108: prio 7 quantum 1514 rate
> 555000Kbit ceil 555000Kbit burst 70901b/8 mpu 0b overhead 0b cburst
> 70901b/8 mpu 0b overhead 0b level 0
>  Sent 46793626324 bytes 57771194 pkt (dropped 29920019, overlimits 0 requeues 0)
>  rate 621714Kbit 97631pps backlog 0b 126p requeues 0
>  lended: 57771068 borrowed: 0 giants: 0
>  tokens: -8 ctokens: -8
> 
> 
> 850 bytes:
> class htb 1:108 parent 1:10 leaf 108: prio 7 quantum 1514 rate
> 555000Kbit ceil 555000Kbit burst 70901b/8 mpu 0b overhead 0b cburst
> 70901b/8 mpu 0b overhead 0b level 0
>  Sent 63422144616 bytes 77714246 pkt (dropped 41012275, overlimits 0 requeues 0)
>  rate 600699Kbit 88756pps backlog 0b 127p requeues 0
>  lended: 77714119 borrowed: 0 giants: 0
>  tokens: -11 ctokens: -11
> 
> 
> 900 bytes:
> class htb 1:108 parent 1:10 leaf 108: prio 7 quantum 1514 rate
> 555000Kbit ceil 555000Kbit burst 70901b/8 mpu 0b overhead 0b cburst
> 70901b/8 mpu 0b overhead 0b level 0
>  Sent 76868403562 bytes 92835297 pkt (dropped 48565133, overlimits 0 requeues 0)
>  rate 636195Kbit 88755pps backlog 0b 126p requeues 0
>  lended: 92835171 borrowed: 0 giants: 0
>  tokens: -7 ctokens: -7
> 
> 
> If you need more values you're free to ask.

Since you're so kind... :-) There is a line in net/sched/sch_htb.c:

#define HTB_HYSTERESIS 1        /* whether to use mode hysteresis for speedup */

Could you change 1 to 0, and repeat these tests above after recompiling?

More thanks,
Jarek P.