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Re: [PATCH 09/12] net: mediatek: increase watchdog_timeo

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> Hi Andrew,
> 
> it is waiting for the watchdog to trigger :-) TBH the 1s seems to be too
> short to for the dma ring length to be flushed and i had to pick some
> value and 5 is used most places.
> 
> it really depends on the amount of packets in the queue, their length
> and the mac setting. the timeout needs to be large enough that it would
> not trigger incorrectly even if the mac is on 10mbit half duplex and all
> frames in the queue were maximum size.

So you are saying there is 5 seconds worth of traffic in the transmit ring.

As a general point, not specific to this driver, is that wise? Isn't
that really bad buffer bloat?

I just wondered what happened to cause it to have 5 seconds worth of
traffic in the transmit ring. Did downstream signal a pause?  But i
thought the byte queue limit was designed to prevent a big backlog in
the transmit queue? At 10/Half, is it not reacting fast enough?  Since
it is half duplex, do you have a lot of traffic coming the other way
and something is not being fair at distributing up and down traffic?

I'm just wondering if by increasing the watchdog to 5 seconds, you are
just hiding a problem.

    Andrew

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[PATCH 00/12] net: mediatek: various small fixes John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
  [PATCH 09/12] net: mediatek: increase watchdog_timeo John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
    Re: [PATCH 09/12] net: mediatek: increase watchdog_timeo Andrew Lunn <andrew@lunn.ch> - 2016-06-05 17:00 +0200
      Re: [PATCH 09/12] net: mediatek: increase watchdog_timeo John Crispin <john@phrozen.org> - 2016-06-06 08:30 +0200
        Re: [PATCH 09/12] net: mediatek: increase watchdog_timeo Andrew Lunn <andrew@lunn.ch> - 2016-06-06 14:30 +0200
          Re: [PATCH 09/12] net: mediatek: increase watchdog_timeo John Crispin <john@phrozen.org> - 2016-06-06 14:40 +0200
  [PATCH 01/12] net: mediatek: fix DQL support John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
    Re: [PATCH 01/12] net: mediatek: fix DQL support David Miller <davem@davemloft.net> - 2016-06-05 09:40 +0200
      Re: [PATCH 01/12] net: mediatek: fix DQL support John Crispin <john@phrozen.org> - 2016-06-06 08:50 +0200
        Re: [PATCH 01/12] net: mediatek: fix DQL support David Miller <davem@davemloft.net> - 2016-06-08 01:10 +0200
          Re: [PATCH 01/12] net: mediatek: fix DQL support Tom Herbert <tom@herbertland.com> - 2016-06-08 01:30 +0200
  [PATCH 07/12] net: mediatek: disable all interrupts during probe John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
  [PATCH 04/12] net: mediatek: invalid buffer lookup in mtk_tx_map() John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
  [PATCH 05/12] net: mediatek: dropped rx packets are not being counted properly John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
  [PATCH 06/12] net: mediatek: add next data pointer coherency protection John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
  [PATCH 08/12] net: mediatek: fix threshold value John Crispin <john@phrozen.org> - 2016-06-05 08:40 +0200
  [PATCH 12/12] net: mediatek: remove superfluous queue wake up call John Crispin <john@phrozen.org> - 2016-06-05 09:10 +0200
  [PATCH 10/12] net: mediatek: fix off by one in the TX ring allocation John Crispin <john@phrozen.org> - 2016-06-05 09:10 +0200
  [PATCH 11/12] net: mediatek: only wake the queue if it is stopped John Crispin <john@phrozen.org> - 2016-06-05 09:10 +0200

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