Date: Wed, 3 May 2006 12:41:42 +0400 (MSD) From: .@babolo.ru To: tpeixoto@widesoft.com.br Cc: Lee Johnston <lee@wildcard.net.uk>, freebsd-net@freebsd.org, Julian Elischer <julian@elischer.org>, mihai@duras.ro Subject: Re: Packet loss with traffic shaper and routing Message-ID: <1146645702.297895.80691.nullmailer@cicuta.babolo.ru> In-Reply-To: <4457F905.4050503@widesoft.com.br>
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> Julian Elischer wrote:
> > tpeixoto@widesoft.com.br wrote:
> >> I think I should give some 'real world' examples.
> >>
> >> /etc/rc.firewall:
> >>
> >> [Ss][Hh][Aa][Pp][Ee][Rr])
> >> setup_loopback
> >>
> >> . /etc/rc.shaper
> >>
> >> ${fwcmd} add 65000 pass all from any to any
> >> ;;
> >>
> >>
> >> /etc/rc.shaper:
> >>
> >> ${fwcmd} pipe 1 config bw 512Kbit/s
> >> ${fwcmd} pipe 2 config bw 512Kbit/s
> >> ${fwcmd} add pipe 1 all from any to any MAC any 00:11:22:33:44:55 in
> >> ${fwcmd} add pipe 2 all from any to any MAC 00:11:22:33:44:55 any out
> >> ${fwcmd} pipe 3 config bw 256Kbit/s
> >> ${fwcmd} pipe 4 config bw 256Kbit/s
> >> ${fwcmd} add pipe 3 all from any to any MAC any 66:77:88:99:aa:bb in
> >> ${fwcmd} add pipe 4 all from any to any MAC 66:77:88:99:aa:bb any out
> >> ${fwcmd} pipe 5 config bw 128Kbit/s
> >> ${fwcmd} pipe 6 config bw 128Kbit/s
> >> ${fwcmd} add pipe 5 all from any to any MAC any 00:01:02:03:04:05 in
> >> ${fwcmd} add pipe 6 all from any to any MAC 00:01:02:03:04:05 any out
> >> ${fwcmd} pipe 7 config bw 512Kbit/s
> >> ${fwcmd} pipe 8 config bw 1024Kbit/s
> >> ${fwcmd} add pipe 7 all from any to any MAC any 06:07:08:09:0a:0b in
> >> ${fwcmd} add pipe 8 all from any to any MAC 06:07:08:09:0a:0b any out
> >> ${fwcmd} pipe 9 config bw 64Kbit/s
> >> ${fwcmd} pipe 10 config bw 64Kbit/s
> >> ${fwcmd} add pipe 9 all from any to any MAC any ab:cd:ef:00:11:22 in
> >> ${fwcmd} add pipe 10 all from any to any MAC ab:cd:ef:00:11:22 any out
> >>
> > OK, so, put the MACs in numerical order:
> >
> > 00:01:02:03:04:05
> > 00:11:22:33:44:55
> > 06:07:08:09:0a:0b
> > 66:77:88:99:aa:bb
> > ab:cd:ef:00:11:22
> >
> > work out MASKS that divide them into a binary set.
> >
> > e.g.
> > 1 skipto 10 all from any to not MAC 00:00:00:00:00:00/8
> > 2 skipto 5 all from any to not MAC 00:01:00:00:00:00/16
> > 3 pipe 1 ip from any to any
> > 5 pipe 2 ip from any to any
> >
> > 10 skipto 12 all from any to not MAC 06:00:00:00:00:00/8
> > 11 pipe 3 all from any to any
> > 12 skipto 14 all from any to not MAC 66:00:00:00:00:00/8
> > 13 pipe 4 all from any to any
> > 14 pipe 5 all from any to any
> >
> > now, if you continue this on, you will run 16 rules to divide the 1600
> > rules up to find the right pipe.
>
> I got your point.
> But what I am telling is that it's not the search or it's not _only_ the
> search in the firewall rules that is making the interrupts go high.
> Please, see below.
In your example each packet walk through the rule set 4 times
1 mac input - abount half a ruleset average
2 ip input - all ruleset, not succesfull
3 ip output - all ruleset, not succesfull
4 mac output - abount half a ruleset average
allow all ip level packets on the ruleset begin and
down proc usage 3 times down.
> >> This example is for 5 clients. We have 1600.
> >> As you can see, there are 2 rules and 2 pipes per host, not 1600.
> >>
> >>
> >> If we try rc.firewall like this...
> >>
> >> setup_loopback
> >> ${fwcmd} add 65000 pass all from any to any
> >>
> >> ... we are ok. Interrupts are low.
> >>
> >> So, following your line of thought, I tried a simple test...
> >>
> >> setup_loopback
> >> ${fwcmd} skipto 65000 ip from any to any MAC any any
> >> . /etc/rc.shaper
> >> ${fwcmd} add 65000 pass all from any to any
> >>
> >> This way, the packets will never pass through shaper rules, but
> >> interrupts
> >> still get very high.
> >>
> >>
> >
> > I don't see how that proves anything
> >
>
> See, if we have just 4 rules in the kernel (3 from setup_loopback +
> allow any to any), we don't have problems with interrupts. They are low,
> about 15~20% with the same traffic.
> But, if we have a 'full' set of rules, let's say 3205 (3 from
> setup_loopback + skipto 65000 + 3200 pipes + allow any to any), where
> only 5 of them are being matched (setup_loopback, 'skipto 65000' and
> 'allow any to any' - the skipto 65000 rule prevents any packet to search
> through my 3200 pipes, right?), we still see interrupts go to 70~90%.
> So, what I am saying is that even if we use skipto rules to create
> 'shortcuts' in the firewall stack, the system still uses lots of
> interrupts. It seems that no matter whether the packets are being
> checked against the rules or not, as long there are so many rules, the
> interrupts will be generated.
>
> Let me know if you got my point.
> I'll do some more tests reducing the number of pipes while keeping the
> same amount of rules to see whether this has some effect in the interrupts.
>
> BTW: I tested your other suggestion about splitting 'in' and 'out' rules
> but it made no difference regarding system interrupts.
>
> Thanks again!
>
>
> >> Basically, we need a solution to shape each MAC address with its
> >> specifics
> >> download e upload speeds.
> >> Given the tests, I don't see how skipto can help, but if you believe that
> >> tablearg (which I am not familiar with) might help, we can try it with
> >> 7.x.
> >>
> >>
> >
> > Tablearg only works with IP addresses.
> >
> >> Thanks.
> >>
> >>
> >>
> >>
> >>> oops, forgot to fix my cut-n- pastes.. corrected triage below..
> >>>
> >>>
> >>> Julian Elischer wrote:
> >>>
> >>>
> >>>> Julian Elischer wrote:
> >>>>
> >>>>
> >>>>> tpeixoto@widesoft.com.br wrote:
> >>>>>
> >>>>>
> >>>>>>> That would do it..
> >>>>>>>
> >>>>>>> In all versions of FreeBSD
> >>>>>>> you can use the skipto rule to make sure that only a few rules are
> >>>>>>> run for any
> >>>>>>> address. Use it to to a binary search for the right pipe.'
> >>>>>>> carefully using 'skipto' and 'table' can make it efficient to do
> >>>>>>> very complex
> >>>>>>> filters like that.
> >>>>>>>
> >>>>>>>
> >>>>>> Sorry, but I didn't realized how to use that as we have to shape
> >>>>>> each user individually, i.e., each MAC address on the LAN has its
> >>>>>> own download and upload speeds.
> >>>>>>
> >>>>>> Could you clarify how to improve the situation with the tools you
> >>>>>> mentioned?
> >>>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>> Assuming you can not use "tablearg" yet (it will make this REALLY
> >>>>> EASY)
> >>>>> then if you have 30 IPs you want to shape from 1.1.1.1 to 1.1.1.30
> >>>>>
> >>>>
> >>>>
> >>>> then, consider the following example using IP addresses.
> >>>>
> >>>>
> >>>>>
> >>>>>
> >>>> ipfw add 1000 skipto 1110 ip from any to 1.1.1.16/28
> >>>> ipfw add 1010 skipto 1032 ip from any to 1.1.1.8/29
> >>>> ipfw add 1012 skipto 1021 ip from any to 1.1.1.4./30
> >>>>
> >>>> ipfw add 1013 [anything] ip from any to 1.1.1.0
> >>>>
> >>>> ipfw add 1014 [anything] ip from any to 1.1.1.1
> >>>> ipfw add 1015 [anything] ip from any to 1.1.1.2
> >>>> ipfw add 1016 [anything] ip from any to 1.1.1.3
> >>>>
> >>>>
> >>>> ipfw add 1021 anything] ip from any to 1.1.1.4
> >>>> ipfw add 1022 [anything] ip from any to 1.1.1.5
> >>>> ipfw add 1023 [anything] ip from any to 1.1.1.6
> >>>> ipfw add 1024 [anything] ip from any to 1.1.1.7
> >>>>
> >>>>
> >>>> ipfw add 1032 skipto 1051 ip from any to 1.1.1.12./30
> >>>>
> >>>> ipfw add 1040 [anything] ip from any to 1.1.1.8
> >>>> ipfw add 1041 [anything] ip from any to 1.1.1.9
> >>>> ipfw add 1042 [anything] ip from any to 1.1.1.10
> >>>> ipfw add 1043 [anything] ip from any to 1.1.1.11
> >>>>
> >>>>
> >>>> ipfw add 1051 [anything] ip from any to 1.1.1.12
> >>>> ipfw add 1052 [anything] ip from any to 1.1.1.13
> >>>> ipfw add 1053 [anything] ip from any to 1.1.1.14
> >>>> ipfw add 1054 [anything] ip from any to 1.1.1.15
> >>>>
> >>>>
> >>>> ipfw add 1110 skipto 1132 ip from any to 1.1.1.24/29
> >>>> ipfw add 1112 skipto 1121 ip from any to 1.1.1.20./30
> >>>> ipfw add 1113 [anything] ip from any to 1.1.1.16
> >>>> ipfw add 1114 [anything] ip from any to 1.1.1.17
> >>>> ipfw add 1115 [anything] ip from any to 1.1.1.18
> >>>>
> >>>> ipfw add 1116 [anything] ip from any to 1.1.1.19
> >>>>
> >>>> ipfw add 1121 anything] ip from any to 1.1.1.20
> >>>> ipfw add 1122 [anything] ip from any to 1.1.1.21
> >>>> ipfw add 1123 [anything] ip from any to 1.1.1.22
> >>>> ipfw add 1124 [anything] ip from any to 1.1.1.23
> >>>>
> >>>>
> >>>> ipfw add 1132 skipto 1151 ip from any to 1.1.1.28./30
> >>>>
> >>>> ipfw add 1140 [anything] ip from any to 1.1.1.24
> >>>> ipfw add 1141 [anything] ip from any to 1.1.1.25
> >>>> ipfw add 1142 [anything] ip from any to 1.1.1.26
> >>>> ipfw add 1143 [anything] ip from any to 1.1.1.27
> >>>>
> >>>>
> >>>> ipfw add 1151 [anything] ip from any to 1.1.1.28
> >>>> ipfw add 1152 [anything] ip from any to 1.1.1.29
> >>>> ipfw add 1153 [anything] ip from any to 1.1.1.30
> >>>> ipfw add 1154 [anything] ip from any to 1.1.1.31
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>> now this example shows a binary search in IP space, written (including
> >>>> bugs) by hand
> >>>> but if you are willing to write a suitable perl script, you can
> >>>> generate a binary search in MAC address space
> >>>> just as easily. just sort them into order and search..
> >>>>
> >>>> I'm not going to try it by had, but for 1600 hosts you should only
> >>>> need to go through
> >>>> 15 rules per host on average, instead of 1600 rules per host.
> >>>> that should cut down your ipfw cpu usage by 1/100
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>> freebsd.org"
> >>>>>
> >>
> >>
> >>
> >
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