We all know that linux is so awesome because we never have to reboot. I've heard of some people saying they've gone a year or more without once rebooting due to the stability of Linux. The longest I've gone on my desktop is a few weeks, but that's due more to all the Thunderstorms in Florida than stability problems. So here's my question - if you have to reboot to load a new kernel, how do you take advantage of kernel updates if you don't reboot? If the answer is - you can't!

Then what do those of you who keep it up for months at a time do?

Not update their kernel all the time. Its not terribly necessery.

updating the kernel is really optional and probably even unnecessary in most cases, unless you've added new hardware or something. and if there's a bug, you can just apply a patch (which i don't believe requires a reboot, but i could be wrong about that). a lot of distros today even still ship with 2.4.x. "if it's not broke, don't fix it."

Its simple they don't update their kernel, on production computers you never update software because a new version has been released. You only update to take advantage of a new feature or because the update has addressed a security issue that specifically affected your system

Do most Linux users actually leave their PCs on all the time then? I've always been in the habit of powering down when I'm not using the PC (saves electricity for one thing not to mention the heat PCs generate over time).

It would save on the time it takes to boot though. I'm not sure if this is normal but my PC takes ages to boot Linux at the start.

I often find that after a time I loose my Linux partition as well (i.e. some kind of corruption occurs which causes the Linux boot to become inaccessible). I've noticed the same with extended Windows partitions as well (so I'm wondering if Windows might be responsible. It's quite unstable on my system). Hopefully that won't happen with this latest version of Mandrake (Mandriva LE 2005).

Depends what the machines used for, some like to leave it running all the time, others like to power down at night.

My machine is left running all the time because besides the convenience of sitting down at it and it being ready to go I also run a webserver, my personal site is hosted on this computer and I also run a mail server, I have a few mail accounts, one with yahoo, another with my domain's registrar and another with my department at uni and they are all setup to forward all mail to my computer.

I don't like to leave my laptop on unnecessarily, that thing can generate some heat and because of the design of a laptop can't dissipate the heat very well

just my opinion, but (imo) computers were meant to run, not meant to be turned off and on all the time. starting up a computer puts a lot of stress on the components, both electrical and thermal (going from cool to warm, etc.) if you use power saving features and turn off your monitor (or use powersaving, sleep, etc.), the extra energy used from leaving it on is really negligible in my experience. most of it is just a few fans.

if your OS boots really slowly, you can usually tweak things to speed up the process. you might be starting a lot of services you don't need, or running ldconfig everytime, etc. but without knowing more about your system it's hard to give any specific recommendations (for me at least, maybe someone else could).

sounds like your hard drive could be going bad if you can't access the partition. or else it needs an overhaul -- an fsck, a repartition to "clean things up" and fix whatever windows did, etc.

Thanks for that synaptical, makes sense.

Usually the partition problems happens over time. For example I've installed Mandrake in the past... used it a bit...then I've used Windows for a while (mainly due to certain project work). A while later when I've gone back to using Linux I've found the Linux partition inaccessible. This is usually weeks or months down the line. I've also had a lot of viruses on my Windows partition lately (cleared up now). I understand they won't effect the Linux OS itself ( that's part of the reason why I'm more interested in moving over to Linux now...) but who knows what they might have one to the boot table etc.

Usually I only update a kernel for security reasons. Most of my hardware I deal with works and is supported under the 2.4.x series kernel. Upgrading in a lot of cases is adding support for hardware that wasn't previously supported, so if your hardware is supported and works, why upgrade? Only upgrade if you use something in the kernel that can affect you by security means.

The latest kernels are not always the most stable so in mission critical applications its best not to use them. The old faithful 2.4.x has been used for ages so the bugs have pretty much been ironed-out making it exceptionally stable.

Well afaik that's not true for desktop components, they are designed not to run 24 hours, whereas server components are designed to be shutdown as seldom as possible, they suffer when they are switched on and off every day.

Desktop components may not have been intended to run 24 hours, but the wear, tear and damage to electrical components is done when they are turned off or on like synaptical says. How many light bulbs have you witness blow whilst turned on, I think you will find they always blow when they are being switched on/off. It is the same for all things electrical.

I have built a few computers including my own personal computer that are being run continuously and they are doing fine

I've got a Pentium 200mhz running on a UPS with an uptime of about 1.5years right now.
It's been humming along since the mid 90's because it's never turned off except when I move. If I turned it off every day it would have died along time ago.
Your pc pulls more power/amps during startup than they do sitting idle all day.
I would recomend running 24/7 as long as you have a good quality UPS. With that your pc will last allot longer.

Really? I didn't realise it pulled that amount amps at start-up. And I used to power down the machine whenever I wasn't using it thinking I was saving energy (even if I left the room for a few hours and came back to it).

I originally planned on using hpdarm (I think that's the name, it's the disk access utility anyway) to slow down disk revs when I wasn't using it and just switching off the monitor when I'm not around. Since then I've gone into the BIOS at startup and did it via APM... I figured it was easier that way since I know what I'm doing there and 'power down' techniques via Linux seem to be really fiddly.

I figure that takes care of the screen (I just switch it off) and disk drive (the two most energy burning peripherals).
Does the CMOS settings overide settings set in Linux (I believe it's ACPI)...? If it does, that's ok.

My only real concern is the CPU which I understand generates a lot of heat over time. I've heard of a 'echo 3> /.../acpi/sleep' thing which puts the CPU to sleep for a while... is that the same sleep function in /sbin?

Also I understand Linux powers down the CPU somewhat when the machine has been running idle for a while. If that's the case I'm hoping the 'sleep' thing above can be avoided as it strikes me as kind of messy.