RE: [PATCH 00/12] add packet generator library and example app

["Morten Brørup" <mb@smartsharesystems.com>]

> From: Bruce Richardson [mailto:bruce.richardson@intel.com]
> Sent: Tuesday, 14 December 2021 15.58
> 
> On Tue, Dec 14, 2021 at 02:12:30PM +0000, Ronan Randles wrote:
> > This patchset introduces a Gen library for DPDK. This library
> provides an easy
> > way to generate traffic in order to test software based network
> components.
> >
> > This library enables the basic functionality required in the traffic
> generator.
> > This includes: raw data setting, packet Tx and Rx, creation and
> destruction of a
> >  Gen instance and various types of data parsing.
> > This functionality is implemented in "lib/gen/rte_gen.c". IPv4
> parsing
> > functionality is also added in "lib/net/rte_ip.c", this is then used
> in the gen
> > library.
> >
> > A sample app is included in "examples/generator" which shows the use
> of the gen
> > library in making a traffic generator. This can be used to generate
> traffic by
> > running the dpdk-generator generator executable. This sample app
> supports
> > runtime stats reporting (/gen/stats) and line rate limiting
> > (/gen/mpps,<target traffic rate in mpps>) through telemetry.py.
> >
> > As more features are added to the gen library, the sample application
> will
> > become more powerful through the "/gen/packet" string parameter
> > (currently supports IP and Ether address setting). This will allow
> every
> > application to generate more complex traffic types in the future
> without
> > changing API.
> >
> 
> I think this is great to see, and sounds a good addition to DPDK. One
> thing
> to address in any v2 is to add more documentation for both the library
> and
> the example app. You need a chapter on the lib added to the programmers
> guide to help others use the library from their code, and a chapter on
> the
> generator example in the example apps guide.
> 
> More general question - if we do have a traffic generator in DPDK,
> would it
> be better in the "app" rather than the examples one? If it's only going
> to
> ever stay a simple example of using the lib, examples might be fine,
> but I
> suspect that it will get quite complicated if people start using it and
> adding more features, in which case a move to the "app" folder might be
> more appropriate. Thoughts?
> 
> /Bruce

If adding a traffic generator lib/app to DPDK itself, it should be able to evolve freely, unencumbered by the DPDK ABI/API stability requirements.

Also, it MUST be optional when building DPDK for production purposes. Consider the security perspective: If a network appliance based on DPDK is compromised by a hacker, you don't want it to include a traffic generator.

-Morten