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Subject: RE: [PATCH 2/7] ath10k: change max RX bundle size from 8 to 32 for sdio
Thread-Topic: [PATCH 2/7] ath10k: change max RX bundle size from 8 to 32 for sdio
From:   Wen Gong <wgong@qti.qualcomm.com>
To:     Dave Taht <dave@taht.net>,
        "ath10k@lists.infradead.org" <ath10k@lists.infradead.org>,
        "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
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Date:   Wed, 4 Sep 2019 04:43:21 +0000
Message-ID: <259d8d7f8c2a4c428ae14ff211c83c1a@aptaiexm02f.ap.qualcomm.com>
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        <1566302108-18219-3-git-send-email-wgong@codeaurora.org>
 <87k1apnyyo.fsf@taht.net>
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> -----Original Message-----
> From: Dave Taht <dave@taht.net>
> Sent: Wednesday, September 4, 2019 12:10 AM
> To: Wen Gong <wgong@qti.qualcomm.com>; ath10k@lists.infradead.org;
> linux-wireless@vger.kernel.org
> Subject: [EXT] Re: [PATCH 2/7] ath10k: change max RX bundle size from 8 t=
o
> 32 for sdio
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> In terms of deeply grokking what increasing buffering to achieve high
> bandwidth on a testbench, vs what it can do to clobber latency in the
> real world at low bandwidths, I tend to point folk at:
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> https://www.youtube.com/watch?v=3DRb-UnHDw02o&t=3D25m40s
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> where I got a whole bunch of hackers to stand up and act like packets
> in an aggregating FIFO wifi queue.
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> This key section is only 8 minutes long, and I promise, y'all laugh
> at least 3 times at the demonstration.
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> At the time, also, the ath10k was so overbuffered that on one test
> I could try to start 100 flows, and only get five.
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> https://lwn.net/Articles/705884/
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> and on my slides:
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> https://blog.linuxplumbersconf.org/2016/ocw//system/presentations/3963/
> original/linuxplumbers_wifi_latency-3Nov.pdf
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Hi Dave,
So your mean is change 8  to 32 will impact latency? It will increase laten=
cy of rx?

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> 0xFFFEFFFF