joda@pdc.kth.se (Johan Danielsson) writes:

>Why do we have both DIAGNOSTIC and DEBUG if the former isn't as
>low-impact as its description suggests?

low-impact doesn't mean no impact.

DIAGNOSTIC tests are usually fast but still cost performance. You
will notice this in critical code paths, e.g. disk I/O and network I/O,
especially on slower systems.

DEBUG tests can be very costly.

Both options _do_ change data size and layout.

Both options even _do_ change behaviour of the kernel (and I am not
talking about panics...).

-- 
-- 
                                Michael van Elst
Internet: mlelstv@serpens.de
                                "A potential Snark may lurk in every tree."