From: Dave Taht <dave.taht@gmail.com>
To: Cake List <cake@lists.bufferbloat.net>
Subject: Re: [Cake] [PATCH net-next] sch_cake: Make gso-splitting configurable from userspace
Date: Thu, 26 Jul 2018 20:24:58 -0700 [thread overview]
Message-ID: <CAA93jw4P-HXrFM1kfbpugCZeoCmBHAtrZXmb4E_uFwKTP1+mBQ@mail.gmail.com> (raw)
In-Reply-To: <1532659510-17385-2-git-send-email-dave.taht@gmail.com>
I should have made that be an RFC. Ah, well.
On Thu, Jul 26, 2018 at 7:45 PM Dave Taht <dave.taht@gmail.com> wrote:
>
> This patch restores cake's deployed behavior at line rate to always
> split gso, and makes gso splitting configurable from userspace.
>
> running cake unlimited (unshaped) at 1gigE, local traffic:
>
> no-split-gso bql limit: 131966
> split-gso bql limit: ~42392-45420
>
> On this 4 stream test splitting gso apart results in halving the
> observed interpacket latency at no loss in throughput.
>
> Summary of tcp_nup test run 'gso-split' (at 2018-07-26 16:03:51.824728):
>
> Ping (ms) ICMP : 0.83 0.81 ms 341
> TCP upload avg : 235.43 235.39 Mbits/s 301
> TCP upload sum : 941.71 941.56 Mbits/s 301
> TCP upload::1 : 235.45 235.43 Mbits/s 271
> TCP upload::2 : 235.45 235.41 Mbits/s 289
> TCP upload::3 : 235.40 235.40 Mbits/s 288
> TCP upload::4 : 235.41 235.40 Mbits/s 291
>
> verses
>
> Summary of tcp_nup test run 'no-split-gso' (at 2018-07-26 16:37:23.563960):
>
> avg median # data pts
> Ping (ms) ICMP : 1.67 1.73 ms 348
> TCP upload avg : 234.56 235.37 Mbits/s 301
> TCP upload sum : 938.24 941.49 Mbits/s 301
> TCP upload::1 : 234.55 235.38 Mbits/s 285
> TCP upload::2 : 234.57 235.37 Mbits/s 286
> TCP upload::3 : 234.58 235.37 Mbits/s 274
> TCP upload::4 : 234.54 235.42 Mbits/s 288
> ---
> net/sched/sch_cake.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
> index 539c949..35fc725 100644
> --- a/net/sched/sch_cake.c
> +++ b/net/sched/sch_cake.c
> @@ -80,7 +80,6 @@
> #define CAKE_QUEUES (1024)
> #define CAKE_FLOW_MASK 63
> #define CAKE_FLOW_NAT_FLAG 64
> -#define CAKE_SPLIT_GSO_THRESHOLD (125000000) /* 1Gbps */
>
> /* struct cobalt_params - contains codel and blue parameters
> * @interval: codel initial drop rate
> @@ -2569,10 +2568,12 @@ static int cake_change(struct Qdisc *sch, struct nlattr *opt,
> if (tb[TCA_CAKE_MEMORY])
> q->buffer_config_limit = nla_get_u32(tb[TCA_CAKE_MEMORY]);
>
> - if (q->rate_bps && q->rate_bps <= CAKE_SPLIT_GSO_THRESHOLD)
> - q->rate_flags |= CAKE_FLAG_SPLIT_GSO;
> - else
> - q->rate_flags &= ~CAKE_FLAG_SPLIT_GSO;
> + if (tb[TCA_CAKE_SPLIT_GSO]) {
> + if (!!nla_get_u32(tb[TCA_CAKE_SPLIT_GSO]))
> + q->rate_flags |= CAKE_FLAG_SPLIT_GSO;
> + else
> + q->rate_flags &= ~CAKE_FLAG_SPLIT_GSO;
> + }
>
> if (q->tins) {
> sch_tree_lock(sch);
> @@ -2608,7 +2609,7 @@ static int cake_init(struct Qdisc *sch, struct nlattr *opt,
> q->target = 5000; /* 5ms: codel RFC argues
> * for 5 to 10% of interval
> */
> -
> + q->rate_flags |= CAKE_FLAG_SPLIT_GSO;
> q->cur_tin = 0;
> q->cur_flow = 0;
>
> --
> 2.7.4
>
--
Dave Täht
CEO, TekLibre, LLC
http://www.teklibre.com
Tel: 1-669-226-2619
next prev parent reply other threads:[~2018-07-27 3:25 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-27 2:45 Dave Taht
2018-07-27 2:45 ` Dave Taht
2018-07-27 3:24 ` Dave Taht [this message]
2018-07-27 20:39 ` David Miller
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
List information: https://lists.bufferbloat.net/postorius/lists/cake.lists.bufferbloat.net/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAA93jw4P-HXrFM1kfbpugCZeoCmBHAtrZXmb4E_uFwKTP1+mBQ@mail.gmail.com \
--to=dave.taht@gmail.com \
--cc=cake@lists.bufferbloat.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
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