The bufferbloat project has been at the problem for a great deal of time
now. As of Linux 3.6, a great deal of the bufferbloat problem on
ethernet has been resolved, with the incorporation (and device driver
support) of BQL (linux 3.3), fq_codel (linux 3.5), and TCP small queues
(3.6)

At linux plumbers in august, there seemed to be consensus that one day
fq_codel could replace pfifo_fast, but it needs a bit more work and
testing in the field. Many of the core netdev people are running it,
there are also tests going on within several large companies.  Work on
improving wifi further is beginning. So, seeking wider deployment, by
default, will get us to where it could ultimately be turned on by
default. Certainly the benefits of the code as it stands now are *quite*
noticible under many workloads particularly on desktops and more than a
few on servers.

Latency under load last year: 
http://www.teklibre.com/~d/bloat/pfifo_fast_vs_sfq_qfq_linear.png
Linux 3.6 PFIFO_FAST: 
https://github.com/tohojo/netperf-wrapper/blob/master/sample_plots/100m_pfifo_fast.png
Linux 3.6 FQ_CODEL: 
https://github.com/tohojo/netperf-wrapper/blob/master/sample_plots/100m_fq_codel.png

Kamal Mostafa, for example, did some testing at canonical earlier this
year and described his reaction in a kernel meeting...

http://www.bufferbloat.net/news/38

I am maintaining a simple script that turns it on, that perhaps could be
shipped by default  for the desktop configuration of ubuntu.

https://github.com/dtaht/deBloat/blob/master/src/debloat.sh

Regardless I encourage people to try fq_codel out, run it day and day
out, as we do, and see if they notice a difference. They will.
Particularly gamers.

Some backing reading material for the work:

Van Jacobson's presentation on codel and fq_codel: 
http://recordings.conf.meetecho.com/Recordings/watch.jsp?recording=IETF84_TSVAREA&chapter=part_3
Linux Plumbers BQL: http://linuxplumbers.ubicast.tv/videos/byte-queue-limits/
Linux Plumbers fq_codel: 
http://linuxplumbers.ubicast.tv/videos/codel-and-fq_codel-fighting-the-delays/ 

TCP small queues in LWN: http://lwn.net/Articles/507065/

...

I note that one of my other "causes" at the moment, is that the enormous
improvements in network performance require, as a base, BQL support in
the underlying device driver. The majority of intel ethernet devices are
BQL-enabled, arm is lacking...

...

For the ongoing work into fixing routers, and cpe, which suffer far
worse than servers and desktops do - see the cerowrt project.

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/940541

Title:
  [needs-packaging] Bufferbloat: Ubuntu doesn't come with bufferbloat
  fixes

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+bug/940541/+subscriptions

-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to