linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Peter Desnoyers <pdesnoyers@chinook.com>
To: Grant Erickson <erick205@umn.edu>
Cc: linuxppc-embedded@lists.linuxppc.org
Subject: Re: Solutions for Fast Software Upgrade in Linux/PPC
Date: Tue, 25 Sep 2001 12:22:15 -0400	[thread overview]
Message-ID: <3BB0AF37.A2041B64@chinook.com> (raw)
In-Reply-To: Pine.SOL.4.20.0109251001370.4999-100000@garnet.tc.umn.edu


I would give some serious thought to the fast reboot idea.

[a related anecdote - a former colleague who worked for Caymam back in
the days when people bought Appletalk routers complained how they were
perceived as much less reliable than the Shiva product, even though the
Shiva crashed much more frequently.  It turns out that the Shiva
rebooted faster than the AppleTalk timeout, while the Cayman box
didn't...]

You can probably separate it into two halves, kernel and application.  I
can boot a 50MHz MBX860 up to /sbin/init in 6 seconds with an NFS root,
so I think 1 or 2 second kernel boot is quite feasible on a faster
machine with data in flash or (already spun up) local disk.  (PCI
scanning will take time, but you should be able to trim it significantly
with knowledge of your hardware)

Application startup depends.  You might investigate having all your
applications use a "checkpoint" or "pre-digested" format for their
configuration files, so that they can load config quickly at boot, and
save configuration before reboot.  This includes whatever application is
going to configure the kernel after boot, which I assume won't be
init+init.d/network+ifconfig etc.

--
.....................................................................
 Peter Desnoyers            (781) 457-1165   pdesnoyers@chinook.com
 Chinook Communications     (617) 661-1979   pjd@fred.cambridge.ma.us
 100 Hayden Ave, Lexington MA 02421

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

  parent reply	other threads:[~2001-09-25 16:22 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-09-25 15:38 Solutions for Fast Software Upgrade in Linux/PPC Grant Erickson
2001-09-25 15:42 ` Mark Hatle
2001-09-25 15:48   ` Jim Thompson
2001-09-25 16:22 ` Peter Desnoyers [this message]
2001-09-26 15:51 ` Josh Huber
2001-09-26 22:53   ` Magnus Damm
2001-09-26 15:52 ` Josh Huber

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=3BB0AF37.A2041B64@chinook.com \
    --to=pdesnoyers@chinook.com \
    --cc=erick205@umn.edu \
    --cc=linuxppc-embedded@lists.linuxppc.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).