Comment 4 for bug 132672

As far as I'm aware, and I don't know a lot, Solaris mode is simply a different way of showing CPU usage. I 'normal' Linux mode you get the % of one CPU (or core or whatever) that a program is using, so two programs that are maxing out one core each of a dual-core system will both show as 100% CPU usage. In Solaris mode, it'll show as 50% each, as the percentages shown are taken as a percentage of all available CPU time.

Basically for a single CPU/core, there should be no difference. On a multi-CPU/core system, Solaris mode shows 100% as 100% or all available CPU time, whereas 'normal' mode shows 100% as being 100% or a specific CPU/core, thus on a quad-core system, the percentages (inc idle) should all add up to 400% on 'normal' and 100% in Solaris.

As I said, I could be wrong but I think that's it. So it's not unnecessary, but it does still need documentation as Tom pointed out.