40% slowdown with dynamic /bin/sh

Dan Nelson dnelson at allantgroup.com
Mon Nov 24 17:22:15 PST 2003

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.
	Dan Nelson
	dnelson at allantgroup.com

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