Worth upgrading my Late 2009 iMac with current OS Mavericks - X 10.9.5 to newer OS?

That question is largely independent of operating system. Your computer is 8 years old. If it is running well, and you think from research it will run a newer OS, then by all means try it.

I cannot say if it will be faster as a result but it should at least be the same speed (maybe a bit faster benefiting from a fresh install).

Soon enough, you will need to replace it anyway.

You can use all OSX, but Yosemite to High Sierra, there is No Handoff Support (Bluetooth 4.0). If you have any issues with the upgrade, the best scenario is backing up the files on the external drive, restoring the OS through the internet and running update over the fresh image.

Thanks John.. as a related matter, one of my pet peeves was that airplay is disabled on Mavericks.  Do you know if Sierra allows airplay on this older machine spec?
that would be enough to get me to upgrade..
cn

I cannot say for sure. Air Play is a connection methodology and should work. I do not know if the speed is high enough to run a TV.

No one can give you the right answer because everything depends on your original image.  4 years ago I had around 250 iMacs running well after the upgrades until Yosemite come up. Most of them failed because of the dodgy Mavericks image we deployed before. After restoring over the internet, Yosemite was working correctly. To get better performance you must move to SSD drive, but do not expect miracles.

No doubt this is dodgy an answer. Will either do a clean Mavericks or Sierra install. No way an upgrade

As to longevity remaining in the machine,I am hopeful that since this is essentially a home machine for iPhotos and some light Office, no end is in sight until the HDD crashes.

I think you should still do an internet restore first because Apple is granting an image based on your device serial number. Sometimes you might install the wrong driver and problems will start popping up like mushrooms after rain.

BN. Pls confirm what you mean by internet restore: you mean download an upgrade to Sierra via App Store?  Not a clean install?  Thx

Shut down the iMac. Use the combination Control + Option + R and power the iMac while you are holding the combination. You have to use LAN cable for internet connection. Hold the combination until globe shows up on the screen. Follow the process, and it might take 1-2 hours to download and install the fresh image. This image will be Apple recommended version with latest drivers. Then download the OSX from the app store and run upgrade over it. With the upgrade, you will still have the best drivers for your model.

BN. Still confused. Sorry.  Do u mean download a fresh install of Mavericks and then upgrade to Sierra vs just a upgrade from my current Mavericks  vs a clean install of Sierra?

When you start the restore over the internet, the initial image might be Lion or Snow Leopard; Apple knows which image is best for your model, so use that image as a start point for updates and upgrades because that is the easiest way to keep the recommended drivers.

Mavericks was a memory hog.  Each subsequent OS release since then used less RAM, although I haven't switched to High Sierra yet because of the change in disk formats.  If you haven't already "purchased" your free OS X version since Mavericks, you won't be able to get it from the App store.  I just sign up to get each one as they come out, even if I don't use it.

You can always just reinstall the current Mac OS without wiping the drive of your personal data.  It will refresh the system files and some things will run better.  I suggest also resetting the SMC and PRAM once in a while.  Things work better after those are done.

If you're experiencing sluggishness in the browser, you may not be able to fix that easily by upgrading your OS.  It's likely due to the extra processes that run in each page.  Install adblock plus and you'll block those resource intensive ads and speed up your browser experience.  I run more than 1 browser, with one set to block all scripting and ads by default.

SB. Thx for the comments:
Would rather have a smaller memory footprint of the OS for obvi reasons.
I have the auto download too of all the OS’s since Mavericks.

I’ve paired down my data: total 1.4 TB now at .9TB and it’s actually improved enough I need to consider doing nothing.

Tempted to do a full upgrade to H Sierra and roll back if not happy.  Thoughts?

Tempted to do a full upgrade to H Sierra and roll back if not happy.  Thoughts?

Yes, that is what I would suggest.

You won't be able to roll back from High Sierra (10.13) without completely wiping the system.  They change the disk format from HFS+ to APFS.  I suggest only going to Sierra (10.12).

Yes but the author has a backup so I see no issue with proceeding

I have a full backup set and no qualms w going back to Mavericks.  Might as well go big.

I wouldn't go all the way back to Mavericks.  Mavericks was the very first of the non-cat versions.  You should try Sierra if you have trouble with High SIerra.  High Sierra is also the first version with APFS.  I usually don't recommend testing the first versions of the major change group, unless you want to be the beta tester.  HFS+ is stable, but APFS is really in the release beta stages.

Did some research on the file format and went clean install onto Sierra. Data restore via cloud and photos upgraded iPhoto library without incident. Running now with no apparent issues. (First 10 monitor sleep recovers had about a 5 second latency but overall system runs cleaner. Big difference in browser responsiveness ).   Thanks to all for their help. !

Great comments.  Went w clean install on Sierra due to caution on high Sierra file management system.

Big gains in os performance (especially browser) and eliminated lots of junk data

Key was to build boot from separate disk for new OS as well as existing OS for piece of mind w back up data off line.

It’s been 8 years and never performed. Should have done this a long time ago.