[Cerowrt-devel] Proper AQM settings for my connection?

[Rich Brown]

On Dec 20, 2013, at 11:32 PM, Hector Ordorica <hechacker1 at gmail.com> wrote:

> I'm running 3.10.13-2 on a WNDR3800, and have used the suggested
> settings from the latest draft:
> 
> http://www.bufferbloat.net/projects/cerowrt/wiki/Setting_up_AQM_for_CeroWrt_310
> 
> I have a 30Mb down / 5Mb upload cable connection.
> 
> With fq_codel, even undershooting network upload bandwidth by more
> than 95%, I'm seeing 500ms excessive upload buffering warnings from
> netalyzr. Download is ok at 130ms. I was previously on a 3.8 release
> and the same was true.

I have seen the same thing, although with different CeroWrt firmware. Netalyzr was reporting
> 500 msec buffering in both directions.

However, I was simultaneously running a ping to Google during that Netalyzr run, and the
ping times started at ~55 msec before I started Netalyzr, and occasionally they would bump
up to 70 or 80 msec, but never the long times that Netzlyzr reported...

I also reported this to the Netalyzr mailing list and they didn’t seem surprised. I’m not sure how to interpret this.

> With pie (and default settings), the buffer warnings go away:
> 
> http://n2.netalyzr.icsi.berkeley.edu/summary/id=43ca208a-32182-9424fd6e-5c5f-42d7-a9ea
> 
> And the connection performs very well while torrenting and gaming.
> 
> Should I try new code? Or can I tweak some variables and/or delay
> options in scripts for codel?

A couple thoughts:

- There have been a bunch of changes between 3.10.13-2 and the current version (3.10.24-5, which seems pretty stable). You might try upgrading. (See the “Rough Notes” at the bottom of http://www.bufferbloat.net/projects/cerowrt/wiki/CeroWrt_310_Release_Notes for the progression of changes).

- Have you tried a more aggressive decrease to the link speeds on the AQM page (say, 85% instead of 95%)?

- Can we get more corroboration from the list about the behavior of Netalyzer?

Rich