moving kickstart forward

[Chris Lumens]

> The ability to evaluate a line or lines based on whether a word appears in
> the kernel cmdline would go a long way.  In Jinja2 style (assuming cmdline
> is an array of words from /proc/cmdline):
> 
> {% if "softraid" in cmdline %}
>  ... whatever software raid args
> {% endif %}

Ah, that is a pretty clever idea.   You'd probably want them to be
namespaced somehow ("ks.softraid", for instance) but that's just a
boring implementation detail.

> The other thing I'd really like to see is the ability to set chunk size for
> software RAID arrays.  It defaults to 512K in mdadm and there's no way to
> specify a size in kickstart.  That default performs terribly in all of the
> workloads where I've tested it.

Our ability to specify options to partitioning tools at various levels
(mkfs.whatever, mount, etc.) is pretty haphazard.  This is basically
because we have only ever added these as-needed, basically for each
single bug that comes in.  It would be worth rethinking everything in
this area - providing ways to set options at all levels, giving these
options obvious names, and perhaps getting rid of kickstart options that
are just pass-throughs to some underlying tool option.

In this particular case, I'd suggest that if 512K is a bad default for
all workloads, it's a bug in mdadm (or wherever sets it) and should be
fixed there.  But your larger point is well taken.

- Chris