Adding more information in the logging files

Hi,

As you know, I've been working on having graphing tools into fio.
I'm running many benchmarks and organize the output by using genfio to name both files and logs.

But, there is always a but, it's impossible while taking a log file to understand in which setup fio ran to produce this log.

So I'd like to add several things inside the log file:
1- the role of each column
2- an header that reports what was fio setting for this log

Pro:
- Taking a log file is enough to understand the performance inside

Cons:
- That would break the current format : I'm thinking about commenting thoses lines.

Any ideas, comments ?

Cheers,