mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Gene Heskett <gene.heskett@verizon.net>
To: Jakob Oestergaard <jakob@unthought.net>,
	Maciej Zenczykowski <maze@cela.pl>
Cc: Dave Brondsema <dave@brondsema.net>, linux-kernel@vger.kernel.org
Subject: Re: uptime reset after about 45 days
Date: Fri, 31 Oct 2003 08:20:04 -0500	[thread overview]
Message-ID: <200310310820.04764.gene.heskett@verizon.net> (raw)
In-Reply-To: <20031031103723.GE10792@unthought.net>

On Friday 31 October 2003 05:37, Jakob Oestergaard wrote:
>On Fri, Oct 31, 2003 at 12:09:25AM +0100, Maciej Zenczykowski wrote:
>...
>
>> Uptime is stored in jiffies which is 32bit on your arch, which
>> results in an overflow after 2^32 clock ticks. TTTicks were 100 HZ
>> till recently (overflow after 470 or so days) now, they're 1000 ->
>> overflows after 45 days.  Doesn't wreck anything except for uptime
>> display - known problem, not worth the trouble fixing it would
>> cause (64 bit values are non-atomic, unless MMX/SSE which isn't
>> allowed in kernel) - however there is (if I'm not mistaken) a
>> patch available wihich fixes this 'problem'.
>>
>> However since it is only a matter of uptime display...
>
>For me it would mean that I got disturbed or woken up by an SMS
> every 45 / (number_of_servers) = (low_number) days, because the
> monitoring system sees that a server suddenly has a 'suspiciously
> low' uptime.
>
>Fix the monitoring system to detect uptime wraps?
>
>Perhaps.  It would be needed for Windows 95 as well, anyway.

Win95 needs more than an uptime patch at that point because the 
keyboard is dead and only a reboot fixes it.  We've been rebooting a 
Win95 wire capture machine every 45-46 days on a schedule because of 
that.

>Still, it's pretty darn pathetic to be required to include
> workarounds in *Linux* apps that would otherwise only be needed for
> '95.
>
>All in my humble oppinion of course.

-- 
Cheers, Gene
AMD K6-III@500mhz 320M
Athlon1600XP@1400mhz  512M
99.27% setiathome rank, not too shabby for a WV hillbilly
Yahoo.com attornies please note, additions to this message
by Gene Heskett are:
Copyright 2003 by Maurice Eugene Heskett, all rights reserved.


  reply	other threads:[~2003-10-31 13:20 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-10-30 22:19 Dave Brondsema
2003-10-30 23:09 ` Maciej Zenczykowski
2003-10-30 23:34   ` Miquel van Smoorenburg
2003-10-31  0:03     ` Robert Love
2003-10-31 10:37   ` Jakob Oestergaard
2003-10-31 13:20     ` Gene Heskett [this message]
2003-10-31 14:59       ` Mike Dresser
2003-10-31 15:26     ` Tim Schmielau
2003-10-31 16:40       ` Tim Schmielau
2003-11-01  3:08         ` Robert Love
2003-11-01  8:35           ` Tim Schmielau

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=200310310820.04764.gene.heskett@verizon.net \
    --to=gene.heskett@verizon.net \
    --cc=dave@brondsema.net \
    --cc=jakob@unthought.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maze@cela.pl \
    /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

all inboxes | Powered by JetHome®