From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Strange latency spikes/TX network stalls on Sun Fire
 X4150(x86) and e1000e
Date: Wed, 06 Jun 2012 07:10:13 +0200
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Cc: Tom Herbert <therbert@google.com>,
	Denys Fedoryshchenko <denys@visp.net.lb>,
	netdev@vger.kernel.org, e1000-devel@lists.sourceforge.net,
	jeffrey.t.kirsher@intel.com, jesse.brandeburg@intel.com,
	davem@davemloft.net
To: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
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On Tue, 2012-05-29 at 23:25 +0900, Hiroaki SHIMODA wrote:

> If I understand the code and spec correctly, TX interrupts are
> generated when TXDCTL.WTHRESH descriptors have been accumulated
> and write backed.
> 
> I tentatively changed the TXDCTL.WTHRESH to 1, then it seems
> that latency spikes are disappear.
> 
> drivers/net/ethernet/intel/e1000e/e1000.h
> @@ -181,7 +181,7 @@ struct e1000_info;
>  #define E1000_TXDCTL_DMA_BURST_ENABLE                          \
>         (E1000_TXDCTL_GRAN | /* set descriptor granularity */  \
>          E1000_TXDCTL_COUNT_DESC |                             \
> -        (5 << 16) | /* wthresh must be +1 more than desired */\
> +        (1 << 16) | /* wthresh must be +1 more than desired */\
>          (1 << 8)  | /* hthresh */                             \
>          0x1f)       /* pthresh */
> 


Was this patch officially submitted ?

Thanks !