ssd swap - high usage of Terabytes Written

[vcsyc]

Is there official info available from Apple for given numbers? TBW or cycles per cell?

 

[Argon_]

What's the warranted number for a 2TB SSD, is it 8x750TBW?

Yes. 2TB*3000 writes per cell. Six petabytes.

 

[Argon_]

Is there official info available from Apple for given numbers? TBW or cycles per cell?

Questions raised about M1 Mac SSD longevity, based on incomplete data | AppleInsider

Complaints about the potential lifespan of Apple Silicon Mac storage are causing concern that the current crop of M1 Macs could stop working within a few years — and have been stoked by unanswered questions, unreliable data, and a silent Apple.

appleinsider.com

The TLC flash is sourced from Toshiba.

 

[k-hawinkler]

Questions raised about M1 Mac SSD longevity, based on incomplete data | AppleInsider

Complaints about the potential lifespan of Apple Silicon Mac storage are causing concern that the current crop of M1 Macs could stop working within a few years — and have been stoked by unanswered questions, unreliable data, and a silent Apple.

appleinsider.com

The TLC flash is sourced from Toshiba.

Many thanks. Quoting from the article:

"Without delving too much into the differences between different types of flash storage, Apple uses Toshiba TLC NAND flash for its drives in the M1 Macs to date. These are rated at about one complete drive-write per day.

The cells in an SSD are durable for around 3,000 read and write cycles in Triple Level Cell-based flash memory chips, though more typically around 10,000 cycles for mid-range Multi Level Cell-based chips. Even so, that still equates to over eight years of usage based on the one complete drive-write per day rating."

So assuming a 10 year lifespan of my M1 Mac mini 16GB/2TB on average it should not have more than this TBW number per month:

6000/120 = 50 TBW/month on average

If that's true I don't see an issue for my situation.

Furthermore, instead of the warranted 3,000 cycles the SSD may potentially last for up to 10,000 cycles, then the TBW issue becomes even more remote, at least for a 2TB SSD only partially filled with actual user data it seems to me.

 

[Argon_]

Many thanks. Quoting from the article:

"Without delving too much into the differences between different types of flash storage, Apple uses Toshiba TLC NAND flash for its drives in the M1 Macs to date. These are rated at about one complete drive-write per day.

The cells in an SSD are durable for around 3,000 read and write cycles in Triple Level Cell-based flash memory chips, though more typically around 10,000 cycles for mid-range Multi Level Cell-based chips. Even so, that still equates to over eight years of usage based on the one complete drive-write per day rating."

So assuming a 10 year lifespan of my M1 Mac mini 16GB/2TB on average it should not have more than this TBW number per month:

6000/120 = 50 TBW/month on average

If that's true I don't see an issue for my situation.

Furthermore, instead of the warranted 3,000 cycles the SSD may potentially last for up to 10,000 cycles, then the TBW issue becomes even more remote, at least for a 2TB SSD only partially filled with actual user data it seems to me.

Per thread ASi performance has tripled in the last five years. If they keep that pace, or even slow to doubling in the next five, upgrading will be a much more attractive option.

 

[k-hawinkler]

Per thread ASi performance has tripled in the last five years. If they keep that pace, or even slow to doubling in the next five, upgrading will be a much more attractive option.

Yup, especially if one uses lower capacity SSDs.

 

[rui no onna]

750 TBW was based on the 3k cycles per cell quoted figure, as a warranted value. 1.5PB would be great.

Apple hasn't released official specs, have they? 3K is typical for 3D TLC but we don't know the exact NAND specifications/configuration used for M1 Macs.

I'm basing 1.5 PBW off Life Percent Used vs TBW in SMART. Back calculating from reported values from forum members, either Apple's using 6K P/E cycle NAND or they've got some hefty over provisioning.

 

[alien3dx]

Are external SSD disks booting now?

for intel mac , i used external but for m1 laptop i never try it. There is few discusiion topic in forum board which success doing it.
** not cross intel/arm bootable.

 

[k-hawinkler]

pistonpilot said:
Are external SSD disks booting now?


Yes, I used a TB3 SSD, copied first M1 Macintosh HD to it with CCC right after formatting to APFS with Disk Utility. Then in Recovery Mode over the Internet installed the latest version of macOS Big Sur.

Apparently this external SSD cannot be updated.
If you have changes to the internal SSD one has to start over from scratch, starting with Disk Utility formatting. Well, that’s my experience so far.

 

[lindros2]

I am pretty shocked by these numbers. You mentioned swap in the title. Do you believe that you are running out of memory and swapping a lot? Have you checked your page outs and calculated that into bytes with vm_stat after a full day's use? Then again you would have to be swapping over 100 GBs per day.... which seems unlikely.

Me too - 1.4TB in 22 hours (??!?!?)

 

[Dockland]

Checked yesterday after about 48 hours since last check Saturday afternoon. 23GB written to disk (11.5GB / day)
(I turned off Spotlight completely Saturday)
Mac Mini M1 16GB/1TB, mostly browsed the web, played some World of Warcraft, watched some YouTube,vids, Apple Music.

 

[4k78]

I have a 16/2TB MPB that went into service on December 8. Transferred over everything from iMac and general browsing and whatnot.

 

[flopticalcube]

Your drive should last until the heat death of the universe.

 

[Marrek]

I think the people complaining are doing something that the rest of us "normal" users are not doing. The only system I have with 2% spare used is my 2018 Intel MacMini w/ a 1TB SSD and 32GB of RAM. My 2019 MacBook Pro 16in is fine and so is my M1 MacMini 16gb 1TB.

All I do is
Safari - youtube, FB, Reddit, cryptocurrency news, etc
Playing League of Legends
Listening to Spotify
Sometimes downloading torrents

There is nothing "special" and still, 7% used SSD ... WHAT.

Edit: just checked it again

Power on Hour: 664
Read: 250TB
Written: 240TB
Used: 8%

Edit2: so when it's time to buy an external HDD to backup my mac?
Also is there any "tool" I can run to see what is causing that many readings/writings?

 

[qap]

If someone doesn't want to rely on a third part app, there's the iostat command, you can use it to monitor the total write and read

M1 MBA 2 month old, 256GB SSD 8Gb RAM: 180GB r/w

Home@Giulio-MacBook-Air ~ % iostat -Id disk0


              disk0


    KB/t xfrs   MB


   27.57 6680658 179860.20

iMac 2019 1 year old, i9, 64Gb RAM, 512Gb SSD: 70GB r/w

Home@Giulio-iMac ~ % iostat -Id disk0


              disk0


    KB/t xfrs   MB


   15.04 4713329 69240.47

In order to check the I/O in real time you can use "sudo iotop" but you have to disable the SIP (I'm too lazy to do it, maybe via recovery boot it works)

EDIT: anyway I don't know if this command reads correctly the datas, I don't care much about the SSD usage because it will last for a lot of years, the trouble is if you fill the SSD.

Another point to consider is the iOS side: since M1 macs are using similar controller to iOS, and on iOS there're tons of read/write from disk, and the iPhone/iPad last years, I don't think it's a big trouble.

Another point is to check if those stats are the same if you have used Migration Assistant or is a brand new installation.

Because I've already ran into some trouble with Photoshop for ARM that doesn't use the correct modules for ARM if you have used Migration Assistant.

 

[Dockland]

One thing regarding the use of swap. I think it's strange that MacOS utilizes swap even when active RAM is below ~25% used. I fired up an Arch Linux install this morning (with a swap partition) just to check, and it's (swap) completely unused, even when stress testing RAM. All default in Arch Linux ($ sysctl vm.swappiness = 60)

 

[CMMChris]

Hector Martin has found a guy on Twitter with the first dead SSD in an M1 machine. It started having issues at around 600TBW. That is about in line with my own SSD lifetime experience. You are likely to start seeing issues at around 500 to 800TBW. Don't expect to reach a Petabyte. At least not on the smaller drives below 1TB capacity.

 

[Dockland]

Hector Martin has found a guy on Twitter with the first dead SSD in an M1 machine. It started having issues at around 600TBW. That is about in line with my own SSD lifetime experience. You are likely to start seeing issues at around 500 to 800TBW. Don't expect to reach a Petabyte. At least not on the smaller drives below 1TB capacity.

It would be interesting, just for the record, to know that user case. The apps/workflow for that specific user/M1.

 

[CMMChris]

Developer AFAIK. Look through his Twitter feed. Don't have a link to the conversation right now (I'm on the phone).

 

[qap]

Could be dead for other reasons anyway. Usually an SSD degrades the speed before death, it doesn’t death for heavy usuage from zero

 

[CMMChris]

It starts using up spare. Once you see spare usage increasing rapidly, you know the SSD will die. Once spare is close to being used up, you can't trust the drive anymore and will likely see first signs of corrupted data.

 

[Dockland]

Could be dead for other reasons anyway. Usually an SSD degrades the speed before death, it doesn’t death for heavy usuage from zero

That is true. SSD do fail sometimes, even if it's somewhat rare.

 

[qap]

That is true. SSD do fail sometimes, even if it's somewhat rare.

Ask to the guys with the old MacBook (like me 😁) were the SSD was failed due to a bad weld (or something similar), the Mac started to show the “?” at boot but only sometimes, then more often, then it dead completely. But it isn’t dead from one day to another, it started to show signals before do it.

At the moment, no M1 users are reporting these signals but Apple should release an update or a statement about this issue.

 

[Spindel]

If someone doesn't want to rely on a third part app, there's the iostat command, you can use it to monitor the total write and read

M1 MBA 2 month old, 256GB SSD 8Gb RAM: 180GB r/w

Home@Giulio-MacBook-Air ~ % iostat -Id disk0


              disk0


    KB/t xfrs   MB


   27.57 6680658 179860.20

iMac 2019 1 year old, i9, 64Gb RAM, 512Gb SSD: 70GB r/w

Home@Giulio-iMac ~ % iostat -Id disk0


              disk0


    KB/t xfrs   MB


   15.04 4713329 69240.47

In order to check the I/O in real time you can use "sudo iotop" but you have to disable the SIP (I'm too lazy to do it, maybe via recovery boot it works)

EDIT: anyway I don't know if this command reads correctly the datas, I don't care much about the SSD usage because it will last for a lot of years, the trouble is if you fill the SSD.

Another point to consider is the iOS side: since M1 macs are using similar controller to iOS, and on iOS there're tons of read/write from disk, and the iPhone/iPad last years, I don't think it's a big trouble.

Another point is to check if those stats are the same if you have used Migration Assistant or is a brand new installation.

Because I've already ran into some trouble with Photoshop for ARM that doesn't use the correct modules for ARM if you have used Migration Assistant.

That output is only since last reboot and basically the same data you get from the activity monitor.

My iostat data currently

disk0


KB/t xfrs MB
6.54 5756357 36790.29

What activity monitor reads:

Add written (skrivna) and read (lästa) data and you get basically the same number as iostats total.

I'm still not worried, but just wanted to point out so you understand what it is you are seeing when using iostat

 

[qap]

Yes, it was only to compare my intel iMac to my M1 Mac. Both as been rebooted on the same time (.2 update), as I previously reported.