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Date: Mon, 28 Jan 2013 09:15:46 -0800
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Subject: Re: ixgbe & msi/x
From: Vijay Singh <vijju.singh@gmail.com>
To: Luigi Rizzo <rizzo@iet.unipi.it>
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> just curious, is this happening under behyve or also native,
> and is it always occurring or it is occasional ?

Native, and it happens when the pps rate is high, even if the
aggregate bandwidth is low.

> I am asking because with netmap when i tried to exploit interrupt
> mitigation (strictly processing incoming traffic only on rx
> interrupts) i noticed packet drops even at relatively low rates,
> which made me suspect that interrupts were either lost or heavily
> delayed.

I am running whatever is in the driver (version 2.4.5) by default.
Since msi/x isnt enabled by default, I have enabled that.

The same test, sustains a *much* higher pps load with legacy
interrupts, so I think that the msi/x interrupt setup is missing
something.

-vijay