40% slowdown with dynamic /bin/sh

[M. Warner Losh]

In message: <20031125012208.GD46761 at dan.emsphone.com>
            Dan Nelson <dnelson at allantgroup.com> writes:
: In the last episode (Nov 25), Daniel O'Connor said:
: > On Tuesday 25 November 2003 06:45, Andrew Gallatin wrote:
: > > So.. forking a dynamic sh is roughly 40% more expensive than
: > > forking a static copy of sh.  This is embarrassing.
: > >
: > > I propose that we at least make /bin/sh static.  (and not add a
: > > /sbin/sh; if we must have a dynamic sh, import pdksh, or put a
: > > dynamically linked sh in /usr/bin/sh).
: > >
: > > I'd greatly prefer that the the dynamic root default be backed out
: > > until a substantial amount of this performance can be recovered.
: > 
: > What _REAL WORLD_ task does this slow down?
: 
: Try timing "cd /usr/ports/www/mozilla-devel ; make clean" with static
: and dynamic /bin.  bsd.port.mk spawns many many many /bin/sh processes.

Maybe you could try it with both and tell us the actual difference in
wall time?

Warner