[adelie-devel] Re: dash as /bin/sh (was: Re: main/ -> system/ + user/ vs aports.git fork [1])

From: Horst G. Burkhardt <horst_at_adelielinux.org>
Date: Mon, 12 Feb 2018 22:58:31 +1100

On Sun, 11 Feb 2018 23:17:30 -0600
"A. Wilcox" <awilfox(a)adelielinux.org> wrote:

> dash is already in system via Alpine main. It's certainly possible to
> provide /bin/sh using dash, but I'm not sure if that is well advised.

You've known me long enough to know that I would never use this as the
primary justification for anything, but: Ubuntu did it years ago and
haven't had trouble. When they implemented the change. system boot
times decreased drastically.

init scripts (the one area one might conceivably have trouble, if
someone gets sloppy) shouldn't be using bashisms anyway (we're aiming
to be POSIX-conformant, no?). And it's during that boot process where
we're going to see the real benefit of doing this - especially on the
older machines we're looking to support.

Per our discussion earlier today, I think we both agree that the
numbers indicate that dash utterly creams bash for execution speed.

also, in anecdata: i've been using dash as system /bin/sh for at least
five years now. I've had precisely zero issues with system management
attributable to that.

It's not as though we would be sacrificing bash or zsh as the user
shell.

> I suppose we could offer the option to advanced users, but I'm not
> sure we should make it all that obvious that one can do it.

I can understand your reticence, but if Ubuntu can pull it off without
the sky falling - they did so eleven years ago now - I think we can
probably discern from that that it's not a horrible idea and is
probably not going to be a source of problems to the end-user, even the
novice.

You saw my numbers from earlier. You verified them yourself. The
difference executing a not-too-complex shell script is measured in
hundredths of seconds on a 1.42GHz PowerPC G4. Think how much
improvement is seen on, say, the 233MHz PowerPC 750 in an iMac/iBook.
Think how much of an improvement would be seen on a Pentium MMX
ThinkPad. It's an invisible change if you're using a modern machine,
but people still getting mileage out of older hardware will appreciate
it.

Best,
 - Horst.
Received on Mon Feb 12 2018 - 11:58:43 UTC

This archive was generated by hypermail 2.4.0 : Sat May 08 2021 - 22:54:40 UTC