Re: [dpdk-dev] tcpdump support in DPDK 2.3

[Matthew Hall <mhall@mhcomputing.net>]

On Wed, Dec 16, 2015 at 11:56:11AM +0000, Bruce Richardson wrote:
> Having this work with any application is one of our primary targets here. 
> The app author should not have to worry too much about getting basic debug 
> support. Even if it doesn't work at 40G small packet rates, you can get a 
> lot of benefit from a scheme that provides functional debugging for an app. 

I think my issue is that I don't think I buy into this particular set of 
assumptions above.

I don't think a capture mechanism that doesn't work right in the real use 
cases of the apps actually buys us much. If all we care about is quickly 
dumping some frames to a pcap for occasional debugging, I already have some C 
code for that I can donate which is a lot less complicated than the trouble 
being proposed for "basic debug support". Or we could use libpcap's 
equivalent... but it's quite a lot more complicated than the code I have.

If we're going to assign engineers to this it's costing somebody a lot of time 
and money. So I'd prefer to get them focused on something that will always 
work even with high loads, such as real bpfjit support.

Matthew.