public inbox for netdev@vger.kernel.org 
 help / color / mirror / Atom feed
From: Patrick McHardy <kaber@trash•net>
To: hadi@cyberus•ca
Cc: netdev@vger•kernel.org
Subject: Re: [RFC NET_SCHED 00/02]: Flexible SFQ flow classification
Date: Wed, 30 May 2007 17:27:45 +0200	[thread overview]
Message-ID: <465D97F1.9090600@trash.net> (raw)
In-Reply-To: <1180536987.4109.19.camel@localhost>

jamal wrote:
> On Wed, 2007-30-05 at 11:40 +0200, Patrick McHardy wrote:
> 
>>One good thing about ESFQ is the more flexible flow classification, but
>>I don't like the concept of having a set of selectable hash functions
>>very much.
>>
> 
> 
> In the spirit of SFQ it is probably ok to do that; 
> [..]
> So if you want to keep that spirit it is ok to do what ESFQ does;
> I think the assumptions will still be valid if you have a gazillion
> queues in todays terms. A number like say 128K may make sense.


Sure. The thing I don't like about the predefined hash functions is
that its unflexible.

>>These patches change SFQ to allow attaching external classifiers and add
>>a new "flow" classifier that allows to classify flows based on an arbitary
>>combination of pre-defined keys. Its probably not the fastest classifier
>>when used with multiple keys, but frankly, I don't think speed is very
>>important in most situations where the current SFQ implementation is used.
> 
> 
> The only one thing i noticed that changes the behavior is the use of
> skb->prio as a selector. I think if you removed that it should be fine.


I don't think thats a problem, it needs to point to the correct major
to have any effect, which can only happen if it is set by the user.
I would prefer to keep it for consistency with other qdiscs.

> Another alternative is to create a brand new FQ qdisc and leave the
> classification to the classifiers.


I created a new classifier to leave classification to the classifiers ..
Not sure exactly why I would need a new qdisc to do that :)

>>It currently does not support perturbation, I didn't want to move this into
>>the classifier, so I need to think about a way to handle it within SFQ.
> 
> 
> It is kind of hard to put it back into the current approach because the
> basic assumptions of ensuring no re-ordering and a "fast" classifier are
> gone.


It doesn't affect performance in any way, but I agree that it doesn't
belong in a classifier. But it should be possible to do it in SFQ.

> I am almost tempted to say go back and write a qdisc called FQ.


Funny, last the this came up you suggested to do basically exactly
what this classifier does, which I thought made sense :)

http://www.mail-archive.com/netdev@vger.kernel.org/msg06801.html

  reply	other threads:[~2007-05-30 15:27 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-05-30  9:40 [RFC NET_SCHED 00/02]: Flexible SFQ flow classification Patrick McHardy
2007-05-30  9:40 ` [RFC NET_SCHED 01/02]: sch_sfq: add support for external classifiers Patrick McHardy
2007-05-30  9:40 ` [RFC NET_SCHED 02/02]: Add flow classifier Patrick McHardy
2007-05-30 11:18 ` [RFC NET_SCHED 00/02]: Flexible SFQ flow classification Andy Furniss
2007-05-30 15:32   ` Patrick McHardy
2007-05-30 16:57     ` Andy Furniss
2007-05-30 14:56 ` jamal
2007-05-30 15:27   ` Patrick McHardy [this message]
2007-05-30 16:10     ` jamal
2007-05-30 16:23       ` Patrick McHardy
2007-05-30 16:34         ` jamal
2007-05-30 16:55           ` Patrick McHardy
2007-05-30 17:02             ` jamal
2007-08-09  4:12   ` Paul E. McKenney

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=465D97F1.9090600@trash.net \
    --to=kaber@trash$(echo .)net \
    --cc=hadi@cyberus$(echo .)ca \
    --cc=netdev@vger$(echo .)kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox