7 ms·

It's gotta be a bug. Hopefully this will get on Apple's radar. Edit: for what it's worth, here's my stats from my 8GB M1 MacBook Air after ~2 months of continu

It's gotta be a bug. Hopefully this will get on Apple's radar. Edit: for what it's worth, here's my stats from my 8GB M1 MacBook Air after ~2 months of continuous heavy usage as my main work machine: Percentage Used: 0% Data Units Read: 4,622,487 [2.36 TB] Data Units Written: 2,301,067 [1.17 TB] Which feels reasonable. So doesn't seem like it affects everyone equally.

xvector 6y ago
> on Apple's radar. (For those not aware, Radar is the name of Apple’s internal bug filing system ;)
- Google234 6y ago
  I believe access is given to outsiders too
  - saagarjha 6y ago
    Only if you’re a partner of some sort, and even then your access is going to be fairly limited.
qeternity 6y ago
My 3 month old 8gb MBP Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 1% Data Units Read: 53,339,111 [27.3 TB] Data Units Written: 49,807,244 [25.5 TB]
- jghn 6y ago
  Here's mine, 8GB M1 Air with 314 power on hours Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 3% Data Units Read: 231,234,195 [118 TB] Data Units Written: 182,951,675 [93.6 TB]
  - merb 6y ago
    btw. this is my macbook pro 16gb 2019 (intel) with ~800 hours: Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 0% Data Units Read: 91,665,449 [46,9 TB] Data Units Written: 88,819,714 [45,4 TB] heavy usage, with vm and i've written to the 1tb nvme disk multiple times and needed to clean stuff to get free space (multiple times)
    - rovr138 6y ago
      > heavy usage, with vm and i've written to the 1tb nvme disk multiple times and needed to clean stuff to get free space (multiple times) This is me all the time. Thank you for validating it's not just me.
  - hmage 6y ago
    check what's in iosnoop. I'm 100% sure it's tons of small (~4kb) writes all the time by some program.
- Reason077 6y ago
  My 3.5 year old 8GB MBP: Available Spare: 79% Available Spare Threshold: 2% Percentage Used: 15% Data Units Read: 251,550,023 [128 TB] Data Units Written: 228,761,896 [117 TB]
cjdell 6y ago
Hmm... My M1 Air 16GB from December is an order of magnitude higher than that, but I do usually have 10 VS Code windows open, lots of Node instances, databases, Slack, and LOTS of browser tabs. Should I be worried? Percentage Used: 1% Data Units Read: 74,899,871 [38.3 TB] Data Units Written: 71,233,417 [36.4 TB]
- marcinzm 6y ago
  The equation is (months machines was used for)/(percentage used). Assuming you've used the machine for 2 months that comes out to 200 months or 16 years left. I suspect you won't care by then.
  - LegitShady 6y ago
    ...assuming linear progression.
  - runeks 6y ago
    25% of the available space gone after four years could very well be a problem. Also, if writes continue at the same rate then wear will increase exponentially, as the same number of writes are distributed over an increasingly smaller amount of space.
    - FPGAhacker 6y ago
      It’s percentage of available wear, not space.
- deleted 6y ago
  [deleted]
- hmage 6y ago
  If you can, run iosnoop in background and note every program that writes 4kb chunks a lot. These are wearing your SSD down. And no, they will not be combined together because most of these shitty apps have O_DIRECT flag set or call fsync() after each write(), making the OS obligated to hit SSD with 4kb write. SSD's don't operate that way, though, a 4kb write is guaranteed to become a bigger write since SSD cell/block is usually either 512kb, or 1mb, or 2mb, or hell even 4mb. So one 4kb per second becomes 4mb per second, and that's 345.6GB/day. Pretty scary how one shitty app can ruin your ssd so fast, huh? I saw google drive app do 50 small writes per second. That's ~2TB/day.
dawnerd 6y ago
16gig model checking in with fairly heavy usage since late November Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 1% Data Units Read: 11,700,881 [5.99 TB] Data Units Written: 38,044,983 [19.4 TB]
vetinari 6y ago
My 50 days old 16GB MBP: Percentage Used: 0% Data Units Read: 11 039 001 [5,65 TB] Data Units Written: 8 341 136 [4,27 TB] That would mean ~87 GB per day, every day. I have about 200 GB data on the drive; that would mean rewriting almost half of it every day. I don't use it that heavily. For comparison, my 2015 MBP has 37 TB written. Since 2015 and about the same usage pattern.
deleted 6y ago
[deleted]
sirn 6y ago
Adding to the data point, this is my 16GB Mac Mini 1TB I've been using as a primary computer since December (so ~3 months). I have been doing some development on this machine as well as porting packages for ARM for MacPorts. I also have Syncthing and Time Machine running. Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 0% Data Units Read: 9,664,566 [4.94 TB] Data Units Written: 5,755,588 [2.94 TB] This sounds to me like a write amplification issue caused by some software as mentioned elsewhere in the thread (first party or third party).

xvector 6y ago

> on Apple's radar. (For those not aware, Radar is the name of Apple’s internal bug filing system ;)

Google234 6y ago
I believe access is given to outsiders too
- saagarjha 6y ago
  Only if you’re a partner of some sort, and even then your access is going to be fairly limited.

qeternity 6y ago

My 3 month old 8gb MBP Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 1% Data Units Read: 53,339,111 [27.3 TB] Data Units Written: 49,807,244 [25.5 TB]

jghn 6y ago
Here's mine, 8GB M1 Air with 314 power on hours Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 3% Data Units Read: 231,234,195 [118 TB] Data Units Written: 182,951,675 [93.6 TB]
- merb 6y ago
  btw. this is my macbook pro 16gb 2019 (intel) with ~800 hours: Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 0% Data Units Read: 91,665,449 [46,9 TB] Data Units Written: 88,819,714 [45,4 TB] heavy usage, with vm and i've written to the 1tb nvme disk multiple times and needed to clean stuff to get free space (multiple times)
  - rovr138 6y ago
    > heavy usage, with vm and i've written to the 1tb nvme disk multiple times and needed to clean stuff to get free space (multiple times) This is me all the time. Thank you for validating it's not just me.
- hmage 6y ago
  check what's in iosnoop. I'm 100% sure it's tons of small (~4kb) writes all the time by some program.
Reason077 6y ago
My 3.5 year old 8GB MBP: Available Spare: 79% Available Spare Threshold: 2% Percentage Used: 15% Data Units Read: 251,550,023 [128 TB] Data Units Written: 228,761,896 [117 TB]

cjdell 6y ago

Hmm... My M1 Air 16GB from December is an order of magnitude higher than that, but I do usually have 10 VS Code windows open, lots of Node instances, databases, Slack, and LOTS of browser tabs. Should I be worried? Percentage Used: 1% Data Units Read: 74,899,871 [38.3 TB] Data Units Written: 71,233,417 [36.4 TB]

marcinzm 6y ago
The equation is (months machines was used for)/(percentage used). Assuming you've used the machine for 2 months that comes out to 200 months or 16 years left. I suspect you won't care by then.
- LegitShady 6y ago
  ...assuming linear progression.
- runeks 6y ago
  25% of the available space gone after four years could very well be a problem. Also, if writes continue at the same rate then wear will increase exponentially, as the same number of writes are distributed over an increasingly smaller amount of space.
  - FPGAhacker 6y ago
    It’s percentage of available wear, not space.
deleted 6y ago
[deleted]
hmage 6y ago
If you can, run iosnoop in background and note every program that writes 4kb chunks a lot. These are wearing your SSD down. And no, they will not be combined together because most of these shitty apps have O_DIRECT flag set or call fsync() after each write(), making the OS obligated to hit SSD with 4kb write. SSD's don't operate that way, though, a 4kb write is guaranteed to become a bigger write since SSD cell/block is usually either 512kb, or 1mb, or 2mb, or hell even 4mb. So one 4kb per second becomes 4mb per second, and that's 345.6GB/day. Pretty scary how one shitty app can ruin your ssd so fast, huh? I saw google drive app do 50 small writes per second. That's ~2TB/day.

dawnerd 6y ago

16gig model checking in with fairly heavy usage since late November Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 1% Data Units Read: 11,700,881 [5.99 TB] Data Units Written: 38,044,983 [19.4 TB]

vetinari 6y ago

My 50 days old 16GB MBP: Percentage Used: 0% Data Units Read: 11 039 001 [5,65 TB] Data Units Written: 8 341 136 [4,27 TB] That would mean ~87 GB per day, every day. I have about 200 GB data on the drive; that would mean rewriting almost half of it every day. I don't use it that heavily. For comparison, my 2015 MBP has 37 TB written. Since 2015 and about the same usage pattern.

deleted 6y ago

[deleted]

sirn 6y ago

Adding to the data point, this is my 16GB Mac Mini 1TB I've been using as a primary computer since December (so ~3 months). I have been doing some development on this machine as well as porting packages for ARM for MacPorts. I also have Syncthing and Time Machine running. Available Spare: 100% Available Spare Threshold: 99% Percentage Used: 0% Data Units Read: 9,664,566 [4.94 TB] Data Units Written: 5,755,588 [2.94 TB] This sounds to me like a write amplification issue caused by some software as mentioned elsewhere in the thread (first party or third party).