[collectd] Adding new DS definitions to existing plugins

[Nic Bellamy]

Hi all,
	short timer listener, long time coder ;-)

For the application we want to use collectd for, we need to keep a bit 
more information about CPU and system states, notably we _are_ 
interested in accounting IRQ/softirq time separately, and also want to 
keep track of total system interrupt count and context switches.

I've whipped up a "works for me" patch for src/cpu.c that adds irq + 
softirq DS definitions to ds_defs[], and updates cpu_read/cpu_submit to 
handle the extra data, and am planning to do a similar thing to 
src/load.c to keep track of IRQ counts and context switches (since it's 
per-system, not per-cpu counts, src/load.c makes sense to me).

I'd like to submit these patches when they're ready, but would be 
interested in any advice regarding how best to handle backwards 
compatibility issues. I couldn't find anything on the website containing 
policies about this kind of thing - can anyone fill me in?

Chers,
	Nic.

-- 
Nic Bellamy,
Head Of Engineering, Vadacom Ltd - http://www.vadacom.co.nz/