Beachball annoyance - considering to downgrade to Yosemite from Sierra (iMac, late 2012)

[Yeroon]

I'm using two different Macs at the moment:a maxed out iMac 27" (late 2012, Core i7" 3.4GHz quadcore, 24GB RAM, 1 TB SSD, NVIDIA GeForce GTX 675MX 1GB GDDR5) and a MacBook Air 13" (early 2014, 1,4GHz i5, 4GB RAM, 256GB SSD, Intel HD5000).

Both systems were upgraded to Sierra in the past months. However, I've noticed a slow-down since El Capitan. I'm seeing the beachball more than I want to. E.g. every few minutes I have to wait several seconds to continue. It mostly concerns large files (in InDesign, Finder, Photoshop, Lightroom) and sometimes programs just freeze and I have to do a forced shutdown. I'm also using several Chrome windows and multiple mail accounts (in Mail).

Something that seems to help is a fresh reboot, but not having to do that was actually a motivation to switch to a Mac (from a pc). But after a few hours, or even minutes, I see that beachball again. I have been looking into my processes and see a lot of activity, even when I'm not using the computer.

Long story short: I erased the SSD of my MacBook Air and started from scratch with Sierra. After having installed my programs, I noticed after only one day, it didn't help. The Mac was slowing down to a very poor level. There even was a delay when typing! Unworkable... I even thought it was broken (hardware-wise). So I erased the Air again and forced it to it's original OS (Mavericks). Then I upgraded to Yosemite and stopped there. Since then everything is running smoothly! I don't know if it's true in every case, but my personal conclusion is that an older MacBook Air is better off with Yosemite than El Capitan or Sierra. I don't need the additional features. My only concern is that I can't always use the latest version of certain apps.

Based on this experience I consider to do the same thing to my iMac (which is my primairy working machine, so important for business). So: make a backup (both Time Machine and a mirror on an external HDD) and then install the original OS and upgrade to Yosemite.

My question is two fold:
1) I can't afford starting from scratch just like my MacBook Air as I have too many processes, data and apps running for my work. So I want to switch to Yosemite on a blank SSD and then restore my data and apps using Time Machine. Does this work out, even though Time Machine has a copy of my Sierra iMac (which I want to restore on Yosemite)?
2) Are there other reasons of concerns not to switch back to an older OS? (e.g. security wise, but I think Yosemite is still being supported)

I'm also interested in your experiences

 

[Fishrrman]

Are you running out of RAM and/or drive space (for VM disk swapping)?

 

[Yeroon]

Are you running out of RAM and/or drive space (for VM disk swapping)?

On my MacBook Air that's a possibility as it has only 4GB of RAM. But this is my portable computer, so I use it for less intensive tasks. Mainly a lot of Chrome browsers and occasionaly some Photoshop/Lightroom. Either way, with Yosemite the machine is performing much better than with El Capitan/Sierra.

My iMac has 24GB RAM and so far the memory usage wasn't close to 100%. I do have a VM (Parallels) but I rarely use it.

On both systems there's at least 100GB free space.

 

[zarathu]

My iMac with 12 gb RAM would slow to a crawl when I got down to less than 500mb left in the ram area. I used onyx and now Dr. Cleaner to optimize the ram and get back the stuff that got lost in programs. it would have to start using virtual ram which was slower. But then you have SSD's in both machines and that should be almost as fast as RAM in the machine.

 

[simon lefisch]

On my MacBook Air that's a possibility as it has only 4GB of RAM. But this is my portable computer, so I use it for less intensive tasks. Mainly a lot of Chrome browsers and occasionaly some Photoshop/Lightroom. Either way, with Yosemite the machine is performing much better than with El Capitan/Sierra.

My iMac has 24GB RAM and so far the memory usage wasn't close to 100%. I do have a VM (Parallels) but I rarely use it.

On both systems there's at least 100GB free space.

I know if you have a spinning HD you should keep at least 15% of the drive free, but not sure if that applies to SSDs as well. You could give it a shot. If you have a 1TB SSD (1024GB) you should have at least 154GB of free space.

Otherwise, something could be failing. Maybe the SSD?

 

[Fishrrman]

OP wrote:
"On my MacBook Air that's a possibility as it has only 4GB of RAM. But this is my portable computer, so I use it for less intensive tasks. Mainly a lot of Chrome browsers and occasionaly some Photoshop/Lightroom. Either way, with Yosemite the machine is performing much better than with El Capitan/Sierra."

I would leave it on Yosemite, if it runs better.

Go with "what works best".

I wouldn't even worry about "the latest and greatest" OS -- I'd use the one that worked best for me.

My opinion only.
Others will disagree.
Some will disagree vehemently.

 

[Yeroon]

Thank you all for your replies. Useful information and opinions! I downloaded Dr. Cleaner (thx zarathu!).

And I've had some new findings. Let me give you an update.

My MacBook Air (early 2014) is still running smoothly on Yosemite. Much better than with Sierra. The 4 GB RAM is at 80% most of the times, which is a concern, especially because it's not upgradable. But I haven't seen the beachball yet, so it seems to work out for now.

My iMac (late 2012, maxed, Sierra) is also working much better now. I freed up space on both the 'Macintosh HD' SSD and an external Thunderbolt drive (2x6GB RAID1). But I also discovered something else. I was checking my internal 1 TB SSD and Mac OS said it was working fine. However, it was performing poorly with BlackMagic Disk Speed Test. Like 15-35MB/s write speeds. It should do +-450MB/s. So I was investigating that and it appeared that TRIM was disabled. What I forgot to mention was that I installed the SSD myself (early 2014). And non-Apple SSD's are not using TRIM by default, which will slow it down fundamentally. Be aware: it can also be turned off after an OS update.

I don't know if this was the problem, but so far my iMac has been running pretty good. I also ordered 16GB additional ram to upgrade the original 8GB RAM and get it from 24GB now to 32GB next week. Especially when running InDesign, Photoshop and Lightroom, this might help.

Again, thanks for thinking with me.