Swap Memory Used is driving me nuts

[vded]

Hello guys, I'm pretty new user on macOS. Couple of months ago bought a Mac mini M2 base model (8/256).

My usage is pretty basic, Safari and internet browsing, YouTube, multimedia, mail, messages (via iPhone), calendar for appointments, reminders when I arrive at work, Apple Music, Apple Podcasts, Pages/Numbers, MoneyBoard for expenses, and messaging apps (FB Messenger/Viber/Discord).

Video/Photo editing no at all.

My friends tell me that I made the wrong decision and that I should go for 16GB RAM. But for my usage and the search I've done before I was pretty sure that I would be fine with the base model. They claim - without something on hand of course - that memory swap usage will tear away my SSD pretty fast.

Unfortunately, this has been so much into my mind, that I find myself clicking numerous times in the day the Stats app option for checking the swap usage which is always around at 1.2GB.

I don't have technical knowledge of macOS and what it right and what wrong.

Should I stick on my newly beloved Mac mini M2? Should I sell it and opt in for 16GB version?

Thanks in advance anyone that answer, regards from sunny 🇬🇷.

 

[MacGizmo]

Your friends are right. And you're also worrying too much.

8GB of RAM is kind of a joke. The OS itself takes nearly ½ of that just to run optimally at its basic level. That being said, you're not running anything that should require much more. Safari will likely be the biggest culprit in the swap use. Every tab you have open will use more and more memory.

I wouldn't sweat it too much, though. If you aren't seeing any issues with crashing or kernel panics (the Mac equivalent of the Windows blue screen of death), then there's probably no problem. Yes, swap will degrade the SSD faster, but that's subjective. If the SSD is going to last 10 years (just a theoretical number), then excessive swap might shorten the life to 8-9 years.

All that being said, I have 64 GB of RAM in my Mac Studio. I am currently running Adobe Photoshop, InDesign, Illustrator and Acrobat, Apple Numbers, Better ZIP, Apple App Store, Apple Reminders, Apple Mail, Safari and Forklift. Those are just the visible apps; I'm also running several menubar apps and background apps. I have zero swap use. So more RAM is always a good thing.

 

[smirking]

Don't listen to your friends. They have what everyone around here has... RAM anxiety. 8GB for your use case should be totally fine and ignore the swap numbers. Most of the time it's pointless. Under normal conditions, MacOS will always use some swap regardless of how much memory you bought.

I took a 2 week hard test drive of an 8GB 13" M1 MBP a couple of summers ago. I have a very heavy workflow. I intentionally used an under-resourced model because I wanted to see if I could run it into the ground.

It held up and then some even though the memory pressure was red the entire time I had it. You'll be fine.

And your SSD is going to be fine too. Chances of you exhausting its lifespan is virtually zero.

 

[Wokis]

Killing an SSD due to swap is virtually unheard of. Some swap write is not an intensive stress for an SSD. The video-editor who went with more RAM but is copying over stuff from external to local on the regular would probably waste more write-cycles. People don't exhaust their SSDs in general.

8GB sets a limit to what the machine is capable of, but it's not going to end itself.

 

[bogdanw]

8GB of RAM is kind of a joke.

No, it's not.
https://forums.macrumors.com/threads/launchd-has-written-40gb-in-7hrs.2384089/post-32042304

 

[Fishrrman]

My solution to the problem of "too much swappin' goin' on":

DISABLE virtual memory disk swapping altogether.
Easily done with terminal.

HOWEVER...
I don't know how well this would work on an m-series Mac with 8gb of RAM.

It worked fine on my 2012 Mini (Intel) with 10gb RAM.
And it works fine on my 2018 Mini (Intel) with 16gb RAM.

Also fine on my 2021 MacBook Pro 14" (m1pro) with 16gb of RAM.

No crashes, no problems.

If I type this in terminal:
sysctl vm.swapusage
... to see how much swap is being used, I get this report:
vm.swapusage: total = 0.00M used = 0.00M free = 0.00M

Works for me.

 

[HDFan]

I don't remember any report of an SSD failing due to excessive swapping but it does make sense to reduce it when you can. If you are in a return period I would be safe and exchange it for 16 GB. This could extend the life of the system if your needs change and you start using memory intensive programs. For example X-Plane on my system at times uses 20 GB of memory, Parallels 8 GB, etc.

Otherwise if it involves a financial hit figure out how soon you would be replacing the machine. If it is a short period of time then the odds of your needs changing are less.

 

[drogon]

I have a 2019 Mac mini with 8GB of memory, earlier this year I upgraded the memory from 8GB to 16GB and I find that swap is still used, as yourself I would have a bunch of safari and Firefox session going and it will still swap 400~500mb while I still have 40% of free memory.

 

[chrfr]

If the computer is performing as you like, and doing what you need it to do, then just ignore the swap numbers.

 

[frqunzfltr]

You are ok, OP.

 

[MacCheetah3]

They claim - without something on hand of course - that memory swap usage will tear away my SSD pretty fast.

Unfortunately, this has been so much into my mind, that I find myself clicking numerous times in the day the Stats app option for checking the swap usage which is always around at 1.2GB.

Zero swap (i.e., sufficient/plenty of RAM) is ideal. However, 1.2GB or thereabout is far from a dire scenario and is unlikely to "tear away my SSD pretty fast.”

More complex answer:

Nobody knows for certain but let’s assume the 256GB (total) NAND chips Apple sources can withstand at least 150 terabytes written (TBW). If so, an average of 42 GB written per day would result in an estimated SSD lifespan of at least 10 years. This is a simplistic calculation, assuming consistent (i.e., linear) wear/degradation.

With that said, you can view your Mac’s storage statistics, including TBW wear, via a program such as DriveDx (which includes a trial period).

Under normal conditions, MacOS will always use some swap regardless of how much memory you bought.

False. “Free” memory (i.e., >0 ) exists because, well, by using a swap file, the OS can clear out some RAM space.

macOS will always use as much RAM as possible. For example, if your computer has 32GB of RAM but the OS, applications, etc only require ~9GB, you could see about 21GB associated with cache. Cached Files is akin to a RAM disk, though in automated form.

 

[JPack]

The rule is, get 8/512 or 16/256. Avoid 8/256 if you can.

Larger SSD to improve longevity from swap. Or more RAM to reduce swap.

The M2 Mac mini is a $499 product. Unless you expect it to last over 5 years, you shouldn't worry about SSD life.

 

[HDFan]

You can guestimate the TBW value for your drive using a program such as DriveDX. For example:

My SSD remaining lifetime is 95%. 5% goes into 95% 19 times.

Data Written 1.2 PB.

1.2 PB x 19 = guestimated 22.8 PBw TBW.

 

[MacCheetah3]

You can guestimate the TBW value for your drive using a program such as DriveDX. For example:

My SSD remaining lifetime is 95%. 5% goes into 95% 19 times.

Data Written 1.2 PB.

1.2 PB x 19 = guestimated 22.8 PBw TBW.

If 1.2 PB is 1.2 petabytes then I may very well be incorrect in my following statements.

While I’m not strongly defending the linear slope calculation; I think, it is more accurate than a one-dimensional linear calculation.

Using my Mac’s SSD SMART data as an example:

• 13.6 TBW
• 99% drive health (as reported/claimed by DriveDx)

- This Mac mini was apparently manufactured in January 2021, though I’ve owned it for about two years (~23 months).

To the calculations:

• 13.6 TBW divided by 2 years equals an average of 6.8 TBW per year. If we were to use an estimated 150 TBW lifespan limit, 150 divided by 6.8 equals about 22 years of expected/guesstimated drive life.

• If 13.6 TBW is one-percent of drive wear, that would equate to a drive/NAND endurance of >1.3 petabytes written.

Both of these guesstimates seem implausible — however, not impossible.

*****

Why a sloped degradation? Exponential wear. Let’s try a simple and scaled example:

• An SSD/NAND of 10 blocks/cells
• Average of 10 gigabytes written per day

At first, each block would endure ~1 GB of wear per day. When one block fails, the remaining blocks would then encounter 1.111… GBW (10 GB divided by 9 blocks) per day. After a second block fails, the demand per remaining cell increases to 1.25 GBW (10 / 8) per day. And so on…

The lifetime of a NAND-flash device is defined by another characteristic: data retention. Data retention is the amount of time that the device can safely store and allow successful retrieval of user data in an unpowered state. When an SSD or other NAND-flash device is brand new, its unpowered data retention will be several years. However, almost like human memory, it gets shorter as it experiences wear and tear, by writing data (data reads do not directly cause wear).

The Joint Electron Device Engineering Council (JEDEC) is the industry group which creates standards and specifications for semiconductor-based devices and assemblies. Micron is a leading member of JEDEC, which defines data retention in a specific way: For SSDs in client applications (like business or personal computers), data retention for an SSD shall be one year, in an unpowered state, stored at 30 °C (86 °F). This should give most computer users plenty of time to retrieve any data from an unused drive after some time on the shelf, if needed.

SSDs and SMART data

A SMART enabled storage drive monitors itself and collects data, and this data can be read and interpreted with the help of utilities capable of reporting the SMART data to the user.

www.crucial.com

 

[CalMin]

If the computer is performing as you like, and doing what you need it to do, then just ignore the swap numbers.

This is the way.

I have an 8gb M2 Air and a 16GB M1Pro. For most daily workflows, they perform identically - even when pushed to silly limits. If the 8gb machine takes a couple seconds longer to do some things, it certainly isn’t noticeable with daily use.

YouTubers and forum posters will show you benchmarks and ”prove” that I am wrong about this. Sure.

Activity monitor just creates anxiety, the reason behind the numbers is very technical, but the truth of it is that what is important is how the machine feels, and my 8 GB machine very rarely if it all feels unresponsive.

Others will tell that 16GB is more future proof. Sure. But unless there is a huge leap in software demands soon, I think it will be fine for at least a few years.

 

[Analog Kid]

I find myself clicking numerous times in the day the Stats app option for checking the swap usage which is always around at 1.2GB.

Based on everything you've said and shown, your friends have no idea what they're talking about and are just trying to sound "in the know" by repeating the kinds of FUD that impress the non-technical.

I'm not familiar with the Stats app UI, but is that dial on the left the memory pressure? It says "1". You essentially have no memory pressure at all. There's nothing to worry about. Stop looking at it.

Activity monitor and these other monitoring apps are there for people who need to understand how to get the most performance out of their systems-- most users won't know what to make of those specs but see them as some sort of alert system. The numbers will fluctuate, it means your system is working.

The 1.2GB of swap doesn't tell you or us anything about how much data you're writing. Having a swap file does absolutely no harm whatsoever. What affects performance is swap rate. If you open a 200GB file and don't touch it for a year, your Mac will eventually swap it out to disk to open up RAM for applications that can make better use of it. Having it there won't hurt performance and it won't hurt your disk any more than any other datafile.

If you were doing extensive calculations on datasets larger than 8GB, then that swap file wouldn't just be sitting there, you'd be hitting it constantly writing and rewriting. You'd notice that as a performance degradation before it started harming your SSD.

If you want to know what your swap rate is, go to terminal and enter 'vm_stat -c 7 10'. The "swapouts" column will tell you how many 16kB pages you've written to disk every 10 seconds for a minute. The first line is the running totals before you launch the command. I'd be interested in seeing the results.

I've never yet heard of an SSD burning out over swap. They're remarkably robust.

The rule is, get 8/512 or 16/256. Avoid 8/256 if you can.

We're presenting FUD in imperative form now? Based on what use case? What budget? What kind of rule says "avoid the product you can find in the store"?

DISABLE virtual memory disk swapping altogether.

You repeat this in every swap thread I can find, but I can't see any reason at all to do this. What's the point of buying something and then intentionally preventing it from working as designed. You're forcing your applications to purge and reconstruct data that it wouldn't otherwise need to. Code is a kind of data that is easy to purge and reconstruct, so I'd expect that you're going to have to keep reading from SSD to get your code pages back into memory.

 

[HDFan]

If 1.2 PB is 1.2 petabytes

Yes.

 

[Fishrrman]

Analog wrote:
"You repeat this in every swap thread I can find, but I can't see any reason at all to do this. What's the point of buying something and then intentionally preventing it from working as designed. You're forcing your applications to purge and reconstruct data that it wouldn't otherwise need to. Code is a kind of data that is easy to purge and reconstruct, so I'd expect that you're going to have to keep reading from SSD to get your code pages back into memory."

I will CONTINUE to post it when I see it necessary. If the moderators don't like such posts, they can remove them.

Have you forgotten the time when Macs had no VM at all?
Or a bit later, when turning it on became optional?

All I can say is that my objective (in disabling VM) was to end the rampant disk swapping that others have complained about and experienced.

And... I did just that.

My Macs (2018 Mini and 2021 MacBook Pro) run just fine with VM disabled.
No problems with that, ever.

But then, I close apps I'm not actively running, and I don't use tabbed browsing, at all -- not ever.

What I do works for me -- very well, indeed.

 

[chrfr]

Have you forgotten the time when Macs had no VM at all?

That’s entirely irrelevant as that was in classic Mac OS, which was not Unix based and shares nothing with the current macOS with regard to memory management or usage.
Disabling swap essentially changes macOS to work more like iOS and has no actual advantages.

 

[Analog Kid]

Analog wrote:
"You repeat this in every swap thread I can find, but I can't see any reason at all to do this. What's the point of buying something and then intentionally preventing it from working as designed. You're forcing your applications to purge and reconstruct data that it wouldn't otherwise need to. Code is a kind of data that is easy to purge and reconstruct, so I'd expect that you're going to have to keep reading from SSD to get your code pages back into memory."

I will CONTINUE to post it when I see it necessary. If the moderators don't like such posts, they can remove them.

Nobody said you couldn't post it, and there's no reason for the mods to remove it, but replying without quoting is the forum equivalent of muttering under your breath...

Have you forgotten the time when Macs had no VM at all?
Or a bit later, when turning it on became optional?

I remember a lot of things without wanting to relive them

All I can say is that my objective (in disabling VM) was to end the rampant disk swapping that others have complained about and experienced.

And... I did just that.

To what benefit? If you can turn it off and still work fine, then "rampant" sounds like a bit of an exaggeration.

My Macs (2018 Mini and 2021 MacBook Pro) run just fine with VM disabled.
No problems with that, ever.

But then, I close apps I'm not actively running, and I don't use tabbed browsing, at all -- not ever.

What I do works for me -- very well, indeed.

That's fine. Your machine your rules. If you want to buy a 2021 MBP with a modern processor running a modern Unix based OS and run it like a Quadra running System 7 out of nostalgia, that's fine. Everything is slower and less convenient that way, though. When you first mentioned it I thought it was an interesting experiment, but I would warn most users away from this path. It can behave unexpectedly and undermines the performance of the machine...

 

[Fishrrman]

" It can behave unexpectedly and undermines the performance of the machine..."

My Macs behave perfectly and are quite fast, thank you very much for your concern...

 

[Feek]

Hello guys, I'm pretty new user on macOS

Don't think of it like Windows where you need to monitor the stats and worry about what they're doing.

If the computer is performing as you like, and doing what you need it to do, then just ignore the swap numbers.

Do this.

Just use the computer and if you think it's underperforming then investigate further. Don't chase the stats.

 

[Analog Kid]

" It can behave unexpectedly and undermines the performance of the machine..."

My Macs behave perfectly and are quite fast, thank you very much for your concern...

Perfectly except you have to keep closing and opening applications and can't use the full feature set of a modern browser, and quite fast but certainly less fast the moment disabling swap matters. Like I said, fun as an experiment but no way for a non-expert user to run daily on a modern architecture.

Anyway, since muttering to the room hoping the person you're replying to doesn't notice is usually an effort to get the last word, I'll end here and let you do that.

 

[vded]

I would like thank you all for your inputs. I'm still learning to use my base Mac mini M2 and the macOS architecture.

I'm 100% relieved from what you said, you helped me a lot to investigate and understand how the things work.

Definitely the Mac is working perfectly for my workflow, no hiccups, no delays!

Of course, you can keep the conversation alive if you would like add something new, help a lot of us understand some new things. 🙂

 

[MacCheetah3]

If 1.2 PB is 1.2 petabytes

Yes.

seem implausible — however, not impossible.

Following further research, that appears to be true: some drives barely make it past the warrantied period/quality, some far exceed.

Samsung 850 Pro SSD Reaches End of Life With 9100 TB Written

No, that isn't a major typo on this article's headline. According to print magazine c't, who conducted a test bench consisting of two pieces each of OCZ's TR150, Crucial's BX 200, Samsung's 750 Evo, Samsung's 850 Pro, SanDisk's Extreme Pro and SanDisk's Ultra II, the last SSD to actually give...

www.techpowerup.com

The SSD Endurance Experiment: They're all dead

techreport.com

The results seem to be based on luck (manufacturing defects a.k.a. “silicon lottery”) and storage use (i.e., not just how much data but in what size chunks are written).

What is the Enterprise SSD Lifetime?

The erasable lifespan of the NAND cell is getting shorter and shorter, which has led to many discussions about SSD longevity.

www.diskmfr.com