[Skiboot] [PATCH] Produce XZ compressed skiboot.lid as part of build

[Stewart Smith]

Michael Neuling <mikey at neuling.org> writes:
> On Mon, 2016-07-04 at 13:27 +1000, Stewart Smith wrote:
>> With a recent HostBoot change, we can have an XZ compressed PAYLOAD
>> that's automagically detected (looking at magic numbers).
>> 
>> This gives us three great benefits:
>> 1) it's transparent, uncompressed skiboot.lid works everywhere
>> 2) it lets us grow greater than 1MB binary, as long as we compress
>>    down to <1MB
>> 3) It speeds up boot. We currently compress down to 230kb rather than
>>    922kb, which is much quicker to read off flash.
>> 
>> This patch produces skiboot.lid.xz alongside standard skiboot.lid.
>
> This increases the built time quite a bit.  On my laptop a build cached in
> ccache currently takes 1.0 sec.  With this patch it increases to 1.5sec, an
> almost 50% increase in build time.
>
> This is still quite fast, but can be a pain if your doing lots of builds
> (say checking bisects doesn't break on a series).
>
> I'm wondering if we could cache it somehow or avoid building it by
> default?

Hrmm..... you could always "make skiboot.lid check" rather than "make
all check"

-- 
Stewart Smith
OPAL Architect, IBM.