Disabling prelink in software builds

[Martin Langhoff]

On Tue, May 17, 2011 at 2:04 PM, Daniel Drake <dsd at laptop.org> wrote:
> prelinking supposedly makes binaries start quicker, but in reality a
> lot of people argue that the gains are minimal compared to the
> headaches (such as this issue) that it creates. Fedora is the only
> major distro that does it by default. Relevant discussion:
> http://lwn.net/Articles/341244/
>
> Any objections to prelink being disabled?

I agree we should disable it for couple of builds, and see how that
fares. If we see no interesting difference, I am all for disabling it.

But it may make a difference -- in that LWN discussion, Arjan Van de Ven, writes

"In Moblin we also use prelink; we found that in addition to the
mentioned arguments, we also can avoid reading whole chunks of
programs from disk into memory, so we save a bunch of time (waiting
for that disk seek) and memory.

Rough estimates on a whole system are between 15% to 20% reduction in
the payload we read from the disk. That was sufficient for us to
decide to use prelink by default."

the discussion that follows his post is interesting. I suspect we
should measure boot time to Sugar and Gnome, and ps_mem.py output
right after boot. Not sure how to measure bytes read from disk easily
-- but they only matter if they delay the boot process significantly
:-)

cheers,


m
-- 
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 martin at laptop.org -- Software Architect - OLPC
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