Date: Thu, 7 Jul 2011 15:28:00 +0200 From: =?ISO-8859-1?Q?Ermal_Lu=E7i?= <eri@freebsd.org> To: Calomel Org <infallibilismindefeasibility@calomel.org> Cc: misc@openbsd.org, freebsd-pf@freebsd.org Subject: Re: pf ALTQ bandwidth limited to a 32bit value (4294Mb) Message-ID: <CAPBZQG1tp9HE7X06YqKGAJJw0y7kOxTgbGnYEQRCMEjCg=AOeQ@mail.gmail.com> In-Reply-To: <20110706152506.GA26334@calomel.org> References: <20110706152506.GA26334@calomel.org>
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On Wed, Jul 6, 2011 at 5:25 PM, Calomel Org
<infallibilismindefeasibility@calomel.org> wrote:
> ALTQ using hfsc is limited to a maximum parent bandwidth of 4294Mb.
> This value is 2^32 or 4,294,967,296 bits. If you set the bandwidth any
> higher, altq will flip back to zero. This "bug" was found when trying
> to test 10 gigabit and 40 gigabit bandwidth models. These tests were
> done on OpenBSD 32bit and 64bit as well as FreeBSD 32bit and 64bit.
>
> If anyone else can verify this independently and agree with the
> results I would be happy to register it as a bug.
>
>
> How to replicate:
>
> A quick test is setting the bandwidth to 4294Mb and doing a pfctl -sq
> to check altq.
>
> altq on $ExtIf bandwidth 4294Mb hfsc queue { ack, web}
> queue root_em0 on em0 bandwidth 4.29Gb priority 0 {ack, web}
>
> Now set the bandwidth to 4295Mb and notice altq has flip to zero and
> add the 32.70Kb difference.
>
> altq on $ExtIf bandwidth 4295Mb hfsc queue { ack, web }
> queue root_em0 on em0 bandwidth 32.70Kb priority 0 {ack, web}
>
> Again, we can set the bandwidth to a multiple of two(2) to 8589Mb.
> The bandwidth value flips to zero once and the result is 4.29Gb.
>
> altq on $ExtIf bandwidth 8589Mb hfsc queue { ack, web}
> queue root_em0 on em0 bandwidth 4.29Gb priority 0 {ack, web}
>
> If we add one more megabit to 8590Mb the value flips twice and we are
> left with 65.41Kb.
>
> altq on $ExtIf bandwidth 8590Mb hfsc queue { ack, web}
> queue root_em0 on em0 bandwidth 65.41Kb priority 0 {ack, web}
>
It is true that there is a limit because of data type used.
Though it cannot be fixed easily on i386 but on amd64 this should work.
Index: sys/contrib/pf/net/pfvar.h
===================================================================
--- sys/contrib/pf/net/pfvar.h (revision 223824)
+++ sys/contrib/pf/net/pfvar.h (working copy)
@@ -1491,13 +1491,13 @@
/* scheduler spec */
u_int8_t scheduler; /* scheduler type */
u_int16_t tbrsize; /* tokenbucket regulator size */
- u_int32_t ifbandwidth; /* interface bandwidth */
+ u_int64_t ifbandwidth; /* interface bandwidth */
/* queue spec */
char qname[PF_QNAME_SIZE]; /* queue name */
char parent[PF_QNAME_SIZE]; /* parent name */
u_int32_t parent_qid; /* parent queue id */
- u_int32_t bandwidth; /* queue bandwidth */
+ u_int64_t bandwidth; /* queue bandwidth */
u_int8_t priority; /* priority */
#ifdef __FreeBSD__
u_int8_t local_flags; /* dynamic interface */
>
> Thanks.
>
> --
> Calomel @ https://calomel.org
> Open Source Research and Reference
> _______________________________________________
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> http://lists.freebsd.org/mailman/listinfo/freebsd-pf
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>
--
Ermal
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