Re: 40% slowdown with dynamic /bin/sh

On Tue, Dec 02, 2003 at 04:48:27PM -0800, Tim Kientzle wrote:
> Bob Willcox wrote:
> >
> >What impact, if any, will this have on those of us that use NIS and
> >still want a statically linked root? I have been using NIS for years ...
> 
> First, let me clarify that I'm advocating moving NIS out of libc in
> the 6.0 timeframe.  Also, I'm not suggesting anyone replace NIS
> with LDAP.  FreeBSD currently has a strong bias for NIS over LDAP; I
> just think we should support both equally.
> 
> How would this affect a static root?
> 
> Make it a lot smaller and faster, for starters.  NIS adds
> as much as 400k each to many programs in /bin and /sbin.
> Over a quarter of a static /bin/sh is from NIS support.
> 
> Does that rule out NIS with a static root?
> 
> Yes, with the current NSS/PAM implementation, although a variety
> of suggestions have been floated around that would make NSS/PAM
> compatible with static binaries.  My personal favorite is to
> implement NSS/PAM daemons to satisfy such requests.  Such daemons
> are surprisingly simple to implement, in my experience.  I'm
> skeptical of efforts to use dlopen() with static binaries; static
> binaries don't have symbol tables, so there's no way to resolve
> references from the dlopen()-ed library back into the executable.
> 
> I'm curious, though.  The single most convincing argument so far in
> favor of a static root has been performance.  Doesn't the NIS network
> overhead swamp any performance gains from static linking?   I suspect
> you have other reasons for wanting a static root.  (Or do you only
> require certain executables to be static, such as /bin/sh?)

Nothing specific. I suppose it's just a space-time tradeoff from my
point of view. With disk sizes what they are today (most of my systems
have a system disk size of 40 GB or more), in my environment reducing
the root filesystem size just isn't a priority.

Bob

> 
> Tim Kientzle

-- 
Bob Willcox          First Law of Procrastination:
bob_at_immure.com           Procrastination shortens the job and places the
Austin, TX           responsibility for its termination on someone else (i.e.,
                     the authority who imposed the deadline).