[175466] in North American Network Operators' Group
Re: Linux: concerns over systemd [OT]
daemon@ATHENA.MIT.EDU (Ricky Beam)
Wed Oct 22 15:34:51 2014
X-Original-To: nanog@nanog.org
To: "Barry Shein" <bzs@world.std.com>
Date: Wed, 22 Oct 2014 15:31:29 -0400
From: "Ricky Beam" <jfbeam@gmail.com>
In-Reply-To: <21575.63462.45782.746718@world.std.com>
Cc: nanog list <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
On Wed, 22 Oct 2014 14:31:02 -0400, Barry Shein <bzs@world.std.com> wrote:
> Perhaps you don't remember the days when an fsck was
> basically mandatory and could take 15-20 minutes on a large disk.
Journaling has all but done away with fsck. You'd have to go *way* back to
have systems that ran a full fsck on every boot -- and in my experience,
you absolutely wanted that fsck.
I've used xfs for over a decade. It doesn't even have an fsck (xfs_check
and xfs_repair, yes, but NO system will ever call them. And as a rule,
never needs to.)
> And you whisk all that away with "it's not really clear to me that
> 'reboots in seconds' is a think to be optimized"????
You're arguing the difference between optimizing a 15min boot into a 5min
boot, vs a 15sec "boot" into a 14sec "boot". The former is an actual
optimization allowing subsystems to start in parallel, in ways that do not
introduce delay. (eg. sendmail startup, used to be the #1 slow down on
solaris) The latter is pure nonsense, with "boot" being measured as when
login pops up -- which is NOT when all the subsystems have actually
completely started.
> To me that's like saying it's not important to try to design so one
> can recover from a network outage in seconds.
Your efforts are better spent avoiding an outage in the first place. If
outages are common enough to be something that needs to be "sped up", then
you've already failed.
