ssd swap - high usage of Terabytes Written

[dave_kor]

You are not the only one, this is exactly the thread I was looking for. Some users have reported EXTREME EXTREME EXTREME writes on their SSDs, over 100TB over 2 months.
For more info check these threads of the people who discovered this issue:

https://twitter.com/i/web/status/1361847686417190918

https://twitter.com/i/web/status/1361722552238841860

https://twitter.com/i/web/status/1361160838854316032

M1 Mac owners are experiencing extremely high SSD writes over short periods of time, likely thanks to aggressive swap

FOR NEWS SITES AND OUTLETS: DON'T MAKE THIS SEEM EXTREME, THE CAUSE IS UNCONFIRMED AND THIS IS NOT A PROBLEM FOR MOST USERS WHO DONT HAMMER THEIR MACHINES Some professional users of the new M1 Macbooks are experiencing extremely high drive writes over relatively short time. IMPORTANT UPDATE: This...

linustechtips.com

https://www.reddit.com/r/mac/comments/lkz3ol
Worse and worse numbers are coming in every day

 

[dave_kor]

And how do you know said software accesses the SMART sensor directly?

There is something off with these numbers.
I'm not worried about this, and if reported numbers by DriveDx are true I only have 1,5 TB of writes since november so definitely not worried for my computers amount of writes to disk.

But as for instance I get reported only 95 power on hours on my SSD, that's about 1 h/day since I got it. That is impossible. I work on this computer, and normal operations means there is constant reading and writing to the hard drive it can not go into hibernation mode that often.

Here are some other screens I posted on another forum.

First of, computer has been on for about 5 hours at this point, some might worry about 34 GB written in this time, hmm there is something going on here:
View attachment 1731398

Secondly:
View attachment 1731399

Why has install deamon written 11,5 GB?
There has been some app updates today but nowhere near that size.

Why is backup reported to have written 8,72 GB?
I backup through TM to my NAS, the number itself probably is correct but not a chance it has written it to the SSD.

Why has OneDrive written 6,5 GB to disk?
I only run on-demand, so files are offline until I need them, I have not worked on that many documents today.

Why has Outlook written almost 900 MB?
For reference I have my personal mail accounts through the default mail app and it has only written about 3 MB to disk.

Thirdly for reference ("växelfil" = swap)
View attachment 1731400


There is absolutely something going on on an OS level. And I'm pretty sure no one in all of these tech forum threads actually have a clue to what it is or how it is effecting the SSDs lifespan.

As I said I'm not worried, but when I started to look at these things I'm becoming really intrigued about what is really happening.

Oh hello there, looks like you on both LTT and MacRumors haha

 

[dave_kor]

what number exactly? "Power on hours" is telling you only about time when disk is working, not when disk is "running".

Most of the time computers are using RAM memory, not SSD/HDD. You can use your computer for 8 hours and see only 1 hour on "power on hours" in SMART sensor.

If I'm wrong - correct me, but this is what I can read on the web.

This is correct. NVMe drives are power-hungry beasts so they usually stay in low power state

 

[Forti]

You are not the only one, this is exactly the thread I was looking for. Some users have reported EXTREME EXTREME EXTREME writes on their SSDs, over 100TB over 2 months.
For more info check these threads of the people who discovered this issue:

https://twitter.com/i/web/status/1361847686417190918

https://twitter.com/i/web/status/1361722552238841860

https://twitter.com/i/web/status/1361160838854316032

M1 Mac owners are experiencing extremely high SSD writes over short periods of time, likely thanks to aggressive swap

FOR NEWS SITES AND OUTLETS: DON'T MAKE THIS SEEM EXTREME, THE CAUSE IS UNCONFIRMED AND THIS IS NOT A PROBLEM FOR MOST USERS WHO DONT HAMMER THEIR MACHINES Some professional users of the new M1 Macbooks are experiencing extremely high drive writes over relatively short time. IMPORTANT UPDATE: This...

linustechtips.com

https://www.reddit.com/r/mac/comments/lkz3ol
Worse and worse numbers are coming in every day

This is sick ?
Tomorrow I will summary everything I know from This thread and from twitter into the first post.

 

[CMMChris]

It doesn't seem to be a general issue with macOS tho and rather caused by some piece of Software because besides users that report enormous TBW on their M1 Macs, there are a lot of people who don't face this problem - like me. Using my M1 MBP since late November 2020 with quite heavy usage. I rarely shut it down and I do lots of video editing (on an external SSD tho). So far TBW count looks absolutely normal:

That's not much different from what I got on the Hackintosh I previously used within that timeframe. Of course I can't guarantee that DriveDx's readout is sane. The power on hours count definitely does not reflect actual power-on time of the MacBook.

 

[Fred Zed]

22 days old, pauper edition 8GB MBP

 

[Spindel]

Data written in Activity Monitor reports the same numbers (e.g. 50GB increase in DriveDx/smartctl = 50GB Activity Monitor Data written) so after verifying, I'm inclined to believe it.

Just today, I booted up my MacBook Air and Activity Monitor reports 18GB Data written. The only thing I did was view photos and create a short Memories clip for my aunt's birthday.

But now we are moving away from the original claim: that this is the swaps fault.

The goal posts are floating.

As I said all along; I’m not worried.

But I have become intrigued why there is, from some apps and processes, so much writing to disk.

Se Post 85 in this thread.

The thing is I have never bothered to ever look at this on my old mac, or on a windows or linux machine. So for me, it’s hard to determine if the 35 GB written in 5 h is abnormal or not.

 

[Spindel]

This is correct. NVMe drives are power-hungry beasts so they usually stay in low power state

But to continue our LTT argument/discussion ( ) look at the I/O activity to disk in activity monitor. Do you even find it plausible for the disk to only have 1 h power on state per day?

 

[rui no onna]

But now we are moving away from the original claim: that this is the swaps fault.

The goal posts are floating.

As I said all along; I’m not worried.

But I have become intrigued why there is, from some apps and processes, so much writing to disk.

Se Post 85 in this thread.

The thing is I have never bothered to ever look at this on my old mac, or on a windows or linux machine. So for me, it’s hard to determine if the 35 GB written in 5 h is abnormal or not.

For Windows, my usage was 15-20GB per day with 24/7 uptime, disk hibernation disabled. I've never owned a Mac before so I don't know what normal disk writes is on that.

I think it's been posited somewhere on these forums that it could be due to indexing and workloads that deal with editing thousands of small files are particularly hard on the storage subsystem.

Found the thread:

Kernel task eats terabyte a day... Anybody else?

Hi guys, Another interesting M1 misbehaviour example... I have noticed that my kernel_task process wrote over 9 terabytes of data within a week... I have a feeling that's a bit much?! Computer spent most of the time sleeping and when on, it was only used for browsing. Yes - I do use on...

forums.macrumors.com

 

[Forti]

But now we are moving away from the original claim: that this is the swaps fault.

The goal posts are floating.

As I said all along; I’m not worried.

But I have become intrigued why there is, from some apps and processes, so much writing to disk.

Se Post 85 in this thread.

The thing is I have never bothered to ever look at this on my old mac, or on a windows or linux machine. So for me, it’s hard to determine if the 35 GB written in 5 h is abnormal or not.

dont get me wrong Please, but I think you dont understand the issue at all.

terabytes written can go high either because you save and delete data on your ssd (e.g. Download a 50gb file and remove it) or by ssd swap.

I dont think the TBW issue is because of „my unusual activity” because there is no „unusual activity” (once again Im comparing my intel and m1 Mac).

plus someone Just Post, that he got 18gb of TBW in couple of mins by doing some basic stuff.

some people also saw huge TBW by kernel process. I personalny didnt notice it so far.

 

[antipodean]

Intrigued by this, I did some investigation of my M1 mini's behaviour (16GB/1TB model). Had it since early November and SMART reports 24TB written, which seemed very high to me. I have used the machine very lightly.

I looked at disk writes in Activity Monitor and found that "cloudd" appears to be the culprit. It was the highest data writes process by a country mile. Swap usage is typically low for me (I didn't really need 16GB RAM, but I like to over-spec my Macs somewhat). Cloudd was ticking away writing GBs while I was watching it. 428GB since a fairly recent reboot, which is an order of magnitude greater than "kernel_task", which I assume is the swap file.

I looked at recent files and noticed that a temp monitoring app I use called TG Pro was constantly writing a small .csv log file, but that its default save location was My Documents, which sits in the iCloud Drive. I unticked "save log file" in the preferences of TG Pro and cloudd has since come under control. Not even 1GB written over a 9-hour period. Previously it was writing like crazy.

I don't know if this was the cause of my higher than normal SSD writes, but I don't need my temps logged and synced to iCloud every second of every day, so killing this is was a no brainer for me. I suspect the constantly changing log file (every second) was causing some problem with the iCloud daemon which resulted in excessive SSD writes.

 

[crevalic]

22 days old, pauper edition 8GB MBP

Weren't you very confident that the software is not able to read the S.M.A.R.T data correctly like a day ago (of course relying on a hunch and ignoring all testing and evidence by others in this thread)?

Or does the software only read the data correctly when it doesn't look like there's a problem?

 

[v654321]

I suggest to try to gather some more structural statistics, including output from the "ac" command:

A record of individual login and logout times are written to the system log by login(8) and launchd(8), respectively. The program ac examines these records and writes the accumulated connect time (in decimal hours) for all logins to the standard output.

Output for my machine, MBP M1, 8C, 8GB RAM, 512GB SSD manufactured 2020-11-09, used as of roughly 3rd week of December for a few hours at max each day, with the occasional day without usage:

$ /usr/local/sbin/smartctl -a /dev/disk3 | egrep "Data|Hours"
Maximum Data Transfer Size: 256 Pages
Data Units Read: 2,062,944 [1.05 TB]
Data Units Written: 1,153,616 [590 GB]
Power On Hours: 17
Media and Data Integrity Errors: 0
$ ac
total 95.93

This translates into roughly 6,2GB SSD write activity per hour that the system records i am actively using the machine. I am a fairly light user and use my M1 MBP as an extra machine next to my other laptops. No heavy usage aside from Microsoft Edge, VS Code, Excel, and regular smaller apps like KeepassXC, WhatsApp, Signal, Coconut Battery, Calculator, Activity Monitor, Messages, Terminal, ... Though these stats are far lower than some of you have reported, i still believe this is quite excessive use of SSD writing, specifically compared to other platforms like Windows and Linux.

Can some of you start adding the ac info as well, including which apps you use constantly/very frequently?

 

[RvXtm]

Lightroom CC and also Classic uses huuuuge amounts of kernel disk writers.
On my m1 mac mini, a normal 1hour session with Lightroom, the app store version (m1 optimised) generates over 1,5 TB written.
This is not importing new stuff, just editing photos and doing corrections.

PS : i did a clean dfu restore of my m1 mini a coupe of times, using latest software clean, same behaviour when opening up Lightroom.

 

[Forti]

➜  ~ /usr/local/sbin/smartctl -a disk0 | egrep "Data|Hours"
Maximum Data Transfer Size:         256 Pages
Data Units Read:                    4,740,501 [2.42 TB]
Data Units Written:                 3,751,548 [1.92 TB]
Power On Hours:                     30
Media and Data Integrity Errors:    0

Today 1.92 TBW, 3 days ago I had 0.9 TBW. What I do more was 12-14 hours of VS code and iOS simulator yesterday.

If the issue is not in apple/m1 itself it maybe because of dozens of different programs that runs under the rosetta 2. Just a thought.

Im planning to collect all the information from here and from the twitter into the first post.

edit: I also switched Spotify from Mac mini to my phone yesterday, but as I can see it doesn't help
edit2: below screen with memory used. When I closed termin with node.js process and VS code - it went down from 12 to 8 GB of used memory.

 

[alien3dx]

➜  ~ /usr/local/sbin/smartctl -a disk0 | egrep "Data|Hours"
Maximum Data Transfer Size:         256 Pages
Data Units Read:                    4,740,501 [2.42 TB]
Data Units Written:                 3,751,548 [1.92 TB]
Power On Hours:                     30
Media and Data Integrity Errors:    0

Today 1.92 TBW, 3 days ago I had 0.9 TBW. What I do more was 12-14 hours of VS code and iOS simulator yesterday.

If the issue is not in apple/m1 itself it maybe because of dozens of different programs that runs under the rosetta 2. Just a thought.

Im planning to collect all the information from here and from the twitter into the first post.

edit: I also switched Spotify from Mac mini to my phone yesterday, but as I can see it doesn't help
edit2: below screen with memory used. When I closed termin with node.js process and VS code - it went down from 12 to 8 GB of used memory.

hmm , for most simple we need apple care if anything happen ?

 

[deeddawg]

hmm , for most simple we need apple care if anything happen ?

First models of a new generation architecture? Kinda figure AC or AC+ is the smart choice on that fact alone.

We'll see what the reality turns out to be as these systems age.

 

[samuelgsilva]

Similar (and far worse!) problems here with 3 M1 Macs.

We recently upgraded some of our old Retina MBP 2015 used for video production (4K media and scratch files on a NAS server, not locally) and insane results here so far!

1. M1 MacBook Air 8GB/256GB (everyday use for pre-production: a couple of Sheets Safari tabs, casual lightweight Premiere on Rosetta 2 editing): 97TBW in 7 weeks!

1. M1 MacBook Air 8GB/256GB (everyday use for pre-production: a couple of Sheets Safari tabs, casual lightweight Premiere editing): 45TBW in 7 weeks!

And the winner…

1. M1 Mac mini 8GB/256GB (everyday use for post-production: heavy Premiere/After/Media Encoder tasks since 04/01): 174TBW in 8 weeks!!

For comparison sake, our Intel i7 MacBook Pro 15 2015 16GB doing the same heavy tasks after 5 years: 85TBW; and our Intel i5 MacBook Pro 13 2013 8GB, after 6 years: 49TBW!!


Another data from Activity Monitor, with a 30h uptime of regular arm64 Safari/Chrome/Excel use: 4,79TBW from kernel_task! ?

Something is clearly off with this kind of disk usage…

 

[gank41]

This all seems so shocking. Not just because of the fact that this happens, but that Apple has either not seen this issue in testing, or they have enough confidence in their hardware that this can continue beyond 2½ years or however long you’re covered under AppleCare. Is it that easy for Apple to service the M1’s and just replace the whole SoC if something happens?

These machines are so new, even with Apple testing them for probably quite some time in secret. I’m curious to hear the stories from people when the “drives” start failing. Apple either has a plan or they’re in for a very large & expensive replacement program.

 

[gank41]

Similar (and far worse!) problems here with 3 M1 Macs.

We recently upgraded some of our old Retina MBP 2015 used for video production (4K media and scratch files on a NAS server, not locally) and insane results here so far!

1. M1 MacBook Air 8GB/256GB (everyday use for pre-production: a couple of Sheets Safari tabs, casual lightweight Premiere on Rosetta 2 editing): 97TBW in 7 weeks!

View attachment 1732208

1. M1 MacBook Air 8GB/256GB (everyday use for pre-production: a couple of Sheets Safari tabs, casual lightweight Premiere editing): 45TBW in 7 weeks!

View attachment 1732207



And the winner…

1. M1 Mac mini 8GB/256GB (everyday use for post-production: heavy Premiere/After/Media Encoder tasks since 04/01): 174TBW in 8 weeks!!

View attachment 1732205

For comparison sake, our Intel i7 MacBook Pro 15 2015 16GB doing the same heavy tasks after 5 years: 85TBW; and our Intel i5 MacBook Pro 13 2013 8GB, after 6 years: 49TBW!!


Another data from Activity Monitor, with a 30h uptime of regular arm64 Safari/Chrome/Excel use: 4,79TBW from kernel_task! ?


View attachment 1732206

Something is clearly off with this kind of disk usage…

I’ve done some similar testing with my M1 MBP 16GB/2TB and my 2015 MBPr 15“ and although my M1 isn’t showing the high amounts you’re seeing, my M1 is already almost ½ of what my 2015 MBP is showing. Crazytown.

 

[CMMChris]

You guys should all team up and compare the software installed on your machines affected by the excessive disk writes. Then we can compare it with M1 devices that don't show this problem. This might help nailing down the root of this issue.

I personally think it has something to do with Rosetta.

 

[blaraka]

For me it happens when I use Lightroom OR Lightroom Classic with full graphic accelaration on. What happens with that setting is that Lightroom starts claiming more and more memory (there's a leak apparently) and then kernel_task just keeps on writing...BRRRR. It was reaching 20GB per 15minutes for me. No apparent slowdown, just killing the SSD.

I don't have much of a problem (8TBW on 1GB SSD after 2.5 months) for now but that's because I've noticed the issue (CRAZY SWAP USAGE) very early thanks to reports of Lightroom users.

For me it's currently manageable with only basic acceleration in Lightroom on and being sort of cautious about running too many things at the same time when Lightroom is opened... With that in mind & with 16GB MBP, swap writes are high but not crazy.That's sort of idiotic though, especially given how powerful those machines are. And based on that I think 8GB M1s are simply unusable for anything beyond "snappy browser and mail".

My theory with that specific case is that Lightroom's GPU acceleration doesn't play well with unified memory and the fact that macOS kernel is very happy to give the apps all memory they want using swap. I actually blamed Adobe for that (I'm pretty vocal here: https://feedback.photoshop.com/conv...m1-macs-with-rosetta/5fd7cefe7288d52d004c5a1c)
Now I'm not sure since apparently the same issue happens with other memory-hungry app.
Adobe is at fault for the memory leak surely but Apple is responsible for the memory management that allows swap to be used too heavily.


EDIT
With all that said and still valid, it seems to me that this definitely happens for everyone using Adobe apps on M1s so that might be a key reason after all.
macOS memory management still shouldn't use SSD to swap like that.

 

[CMMChris]

Apparently the same issue happens with any memory-hungry app.

Nope. I would have high TBW as well in that case using Final Cut. I guess Rosetta could be the problem. I am personally not using any demanding Apps that require Rosetta and my machine is fine.

 

[gank41]

You guys should all team up and compare the software installed on your machines affected by the excessive disk writes. Then we can compare it with M1 devices that don't show this problem. This might help nailing down the root of this issue.

I personally think it has something to do with Rosetta.

I agree with Rosetta possibly writing more data to disk than needed, that could potentially be fixed with an update.

As for any potential apps as the culprit, I use Logic Pro often to record between 4-7 or so GB a week. I don’t use any photo effect apps, but I do also have a large photo library I add to frequently (37,000+ photos).

I’m wondering if some resource monitoring apps like iStat Menus or maybe Little Snitch are writing to a log file repeatedly causing a file size to grow and grow and then maybe purge on logout/restart? Or maybe being connected to an External Display causing higher GPU usage and then having to write to the disk? Under “normal” scenarios with a standard HDD or SSD it’s a little easier to rule stuff out. With an SoC like this, though, it could be something else or all of the above.

 

[blaraka]

Nope. I would have high TBW as well in that case using Final Cut. I guess Rosetta could be the problem. I am personally not using any demanding Apps that require Rosetta and my machine is fine.

The same thing happens with Adobe Lightroom (CC) that is native. Basically behaviour of memory usage and swapping looks more or less the same with Lightroom Classic through Rosetta and Lightroom M1 native.
It's enough to scroll through the images in Develop mode (with GPU acceleration on) to see memory usage slowly growing ad infinity and causing swap writes.

But I guess heavy Rosetta apps / Adobe memory leaking apps might offer a path to explanation.

Still, with all the sandboxing that Apple enforces in macOS, I believe it should protect customers from this kind of stuff as well.

EDIT

One more thing regarding Adobe's GPU acceleration. It "sees" M1's GPU as 10.5GB RAM one. And it instantly reserves all of that memory when full GPU acceleration is on. No wonder macOS needs to use SWAP.
It seems actually the same thing happens when you turn on full GPU acceleration on discrete GPUs. I've seen people complaining about GPU not being able to serve other tasks at all.