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Subject: Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and
 OOM
To: Boris Ostrovsky <boris.ostrovsky@oracle.com>
References: <1484771149-12699-1-git-send-email-vineethp@u480fcf3b67f557f68df1.ant.amazon.com>
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CC: <linux-kernel@vger.kernel.org>, David Miller <davem@davemloft.net>,
        <netdev@vger.kernel.org>, Wei Liu <wei.liu2@citrix.com>,
        Paul Durrant <paul.durrant@citrix.com>,
        xen-devel <xen-devel@lists.xen.org>
From: Vineeth Remanan Pillai <vineethp@amazon.com>
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Date: Tue, 31 Jan 2017 08:47:25 -0800
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On 01/30/2017 08:47 AM, Vineeth Remanan Pillai wrote:
>
> On 01/29/2017 03:09 PM, Boris Ostrovsky wrote:
>>
>> There are couple of problems with this patch.
>> 1. The 'if' clause now evaluates to true on pretty much every call to 
>> xennet_alloc_rx_buffers().
> Thanks for catching this. In my testing I did not notice this - mostly 
> because of the nature of the workload in my testing.
I am working on a patch to revert to the old behavior and solve the Rx 
stall issue by scheduling the timer if any of the following
conditions are true:
  - unconsumed requests + new requests < NET_RX_SLOTS_MIN (old behavior)
  - skb allocations fail

Will send out the patch by next week after I can do some testing.

Thanks,
Vineeth