I turn off my desktop machine every Friday afternoon. We have many servers with up-times exceeding three years

We should rather track downtime.

My two systems run 24/7. I love instant-on and donate the power and CPU cycles to the Folding@Home project, https://folding.stanford.edu/. In fact, with a mini-plug, the SuSE Linux Users team (#35676) could surely use a few more cpus.

But I guess I had a fairly recent kernel upgrade as the run time is only 24 days. I know I've seen more than six months.

Cheers,
Dave

Would be longer but:
always up to date, so if a kernel reboot is needed, it gets it, also any other software requiring reboot (not often)
also on a 4 week Clonezilla cycle for complete (4 OSs) image.
So never longer than 28 days.

I like that idea!
Let's see, how long does a kernel reboot take? Not long.
Backup image (offline) a little longer, so not much.
Lots of CPU time to Mersenne project and some to me.

Ahh, I'm always testing stuff and updating kernel on my desktop/server. But I recently retired a customer's server that was up for over 700 days running Ubuntu.

I only turn my main pc off at night during summer to stop heat build-up in my unit

11-30 days only because I choose to reboot for kernel updates. And that's only for security paranoia. Being hacked is a waste of time. Rebooting is cheaper.

At work, most were shutdown only for annual power maintenance shutdowns or EPO (emergency power off) system tests.

In the interest of saving power, and because my new machine boots so quickly (about 35 sec from initial button press), I just shut down when I'm through and start fresh in the morning. I used to stay up for weeks or longer, but no more. Times change!

I do agree with most of the posters here.

I run Fedora 23 as my primary OS which basically means a reboot every 5 to 15 days. Still for my desktop a reboot normally means less than 60 seconds which actually includes the reboot, me logging in and actually doing something. IMHO SSD's are great when used as your system disk

Since I am not into over-clocking or gaming (I don't mind playing a retro game on occasion) I only use my motherboard's graphics (Z170 chip-set) since my machine consumes less then 40W (includes CPU, Memory, motherboard, disks and power supply) even when I am doing minor work such as surfing the WEB. If I run some video manipulation software my machine rarely consumes more that 140W.

Power conservation. So it runs a few hours at most before next shut down.

For several years most of my work is at home and even when I'm out it is common that I wish to connect remotely. For these and the effects of hard drive cold restarts, I leave my main (Slackware) box on all the time. Shortly after an installation or system upgrade I research and get the newest longterm kernel release and custom build it so I don't change kernels often. I do sometimes boot other distros and (less with very passing year) Windows so my Poll answer is based on Current Uptime of 93 days. The longest period was just short of 16 months, but ~1 year has not been uncommon.

I thought we already had this poll

I know the poll states

the trouble is. My motorcycle shop media box stays up more than my Linux center in my man cave office room in my house.

So here is uptime so far since last upgrade reboot on the media center. I will update this post as time passes.

The 2 users are me. This is my stereo receiver in the motorcycle shop that runs 24/7 till a reboot on upgrade. Not my main box.

since the last blackout [media center pc]: