From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: [PATCH v2 00/13] introduce fail-safe PMD
Date: Thu, 9 Mar 2017 09:15:14 +0000
Message-ID: <20170309091514.GB302480@bricha3-MOBL3.ger.corp.intel.com>
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Cc: Gaetan Rivet <gaetan.rivet@6wind.com>, dev@dpdk.org,
 Thomas Monjalon <thomas.monjalon@6wind.com>,
 Adrien Mazarguil <adrien.mazarguil@6wind.com>
To: Neil Horman <nhorman@tuxdriver.com>
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On Wed, Mar 08, 2017 at 11:54:02AM -0500, Neil Horman wrote:
> On Wed, Mar 08, 2017 at 04:15:33PM +0100, Gaetan Rivet wrote:
> > This PMD intercepts and manages Ethernet device removal events issued by
> > slave PMDs and re-initializes them transparently when brought back so that
> > existing applications do not need to be modified to benefit from true
> > hot-plugging support.
> > 
> > The stacked PMD approach shares many similarities with the bonding PMD but
> > with a different purpose. While bonding provides the ability to group
> > several links into a single logical device for enhanced throughput and
> > supports fail-over at link level, this one manages the sudden disappearance
> > of the underlying device; it guarantees applications face a valid device in
> > working order at all times.
> > 
> Why not just add this feature to the bonding pmd then?  A bond is perfectly
> capable of handling the trivial case of a single underlying device, and adding
> an option to make the underly slave 'persistent' seem both much simpler in terms
> of implementation and code size, than adding an entire new pmd, along with its
> supporting code.
> 
> Neil
>
+1 
I don't like the idea of having multiple PMDs in DPDK to handle
combining multiple other devices into one.

/Bruce