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From: David Lang <david@lang.hm>
To: "Toke Høiland-Jørgensen" <toke@toke.dk>
Cc: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>,
	"David Lang" <david@lang.hm>,
	cerowrt-devel <cerowrt-devel@lists.bufferbloat.net>,
	"David P. Reed" <dpreed@deepplum.com>,
	bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] [Cerowrt-devel] uplink bufferbloat and scheduling problems
Date: Thu, 2 Dec 2021 01:09:49 -0800 (PST)	[thread overview]
Message-ID: <34643258-8or9-sppr-179-307553o21p20@ynat.uz> (raw)
In-Reply-To: <87mtlj6f4g.fsf@toke.dk>

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On Thu, 2 Dec 2021, Toke Høiland-Jørgensen wrote:

> "Valdis Klētnieks" <valdis.kletnieks@vt.edu> writes:
>
>> On Wed, 01 Dec 2021 13:09:46 -0800, David Lang said:
>>
>>> with wifi where you can transmit multiple packets in one airtime slot, you need
>>> enough buffer to handle the entire burst.
>>
>> OK, I'll bite... roughly how many min-sized or max-sized packets can you fit
>> into one slot?
>
> On 802.11n, 64kB; on 802.11ac, 4MB(!); on 802.11ax, no idea - the same as 802.11ac?

As I understnad it, 802.11ax can do 16MB (4MB to each of 4 different endpoints)

This is made significantly messier because the headers for each transmission are 
sent at FAR slower rates than the data can be, so if you send a single 64 byte 
packet in a timeslot that could send 4/16MB, it's not a matter of taking 
1/128,000 of the time (the ratio of the data), it's more like 1/2 of the 
time.

So it's really valuable for overall throughput to fill those transmit slots 
rather than having the data trickle out over many slots.

David Lang

  reply	other threads:[~2021-12-02  9:09 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-01  0:13 [Bloat] " Dave Taht
2021-12-01 20:26 ` [Bloat] [Cerowrt-devel] " David P. Reed
2021-12-01 21:06   ` David Lang
2021-12-01 21:09   ` David Lang
2021-12-01 22:28     ` Valdis Klētnieks
2021-12-02  0:10       ` Toke Høiland-Jørgensen
2021-12-02  9:09         ` David Lang [this message]
2021-12-02 17:20     ` Dave Collier-Brown
2021-12-02 19:33       ` David Lang
2021-12-02  8:11   ` Jan Ceuleers
2021-12-02  8:45   ` Sebastian Moeller

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