You might have seen my video about how long
the SSD in your Mac is going to last.
If you haven't, it's linked in the description.
But in this video, I'm going to show you how
to check the health of your Mac's SSD
and see how much data it's written over its entire lifetime
and potentially, how much longer it's going to last.
Okay, so I'm going to be using a number
of tools and techniques in this video.
They're all free to use
and they're not particularly complicated to use either.
Let's start with something called Smartmontools
which allows you to tap into the Self-Monitoring Analysis
and Reporting Technology System known as SMART
that's built into your SSD.
So first of all, you need to download Smartmontools.
Now I will link this website down below,
but once you're on smartmontools.org,
you need to come over here
to the Jump to section and click Download.
Then in the table of contents, navigate down
to Install the OSX/Darwin package and click on that.
And then up here where it says,
download and run the latest smartmontools.dmg image,
you want to click where it says Here.
That will take you to the next page.
And then you want to click on this green button
which says Download Latest Version.
Once the download has finished,
you want to go into your Downloads folder.
You want to double click on the smartmontools.pkg.
If you do get an error message like this one,
just click Okay, come back to the .pkg file,
right-click, click Open, and then click Open again.
Now there's nothing bad about Smartmontools.
This is basically just macOS double-checking
if you want to install this or not.
Next we're going to open up an application called Terminal.
Now, if you guys have Windows before,
this is essentially the macOS version
of Windows Command or Windows Terminal.
So to open this up,
a really quick shortcut is actually holding
down Command on the keyboard,
pressing the space button, and then typing in terminal,
and then you can see terminal pop up there.
We're going to click on that.
And I'm just going to resize this window
to make it a little easier for you to read.
Now, the first thing we want to do is make sure
we're in the correct directory in Terminal.
So we're going to type cd space forward slash USR
slash local slash sbin,
and we're going to hit the Return key on the keyboard.
And you can see we are now in the sbin directory
which means we can actually load up Smartmontools.
Now I will also include all of these commands written
in the description down below.
Just bear in mind,
if you try to copy and paste those commands
from the description into Terminal, it probably won't work.
You might get an error.
If that's the case, guys, just type it manually
into Terminal because sometimes Terminal
just doesn't like it when you copy and paste,
so just bear that in mind.
So next, we're going to type ls space,
hyphen l and hit the Return key.
This will just allow us to double-check
if Smartmontools has installed correctly.
And as you can see here,
we do have smartctl and also smartd, so that's all good.
Smartctl just allows you to essentially talk
to the SSD inside your Mac directly.
But to do that, first of all,
we need to know what the SSD is actually called.
So we can come in here
and type in diskutil space list.
Hit the Return key.
And GUID underscore partition underscore scheme.
That is going to be our disk.
You can verify this by seeing the size.
This is a four terabyte SSD. So that's the disk we want.
And you can see the identifier or the name is disk0.
Next, we're going to type full stop,
forward slash smartctl space,
hyphen a space forward slash dev forward slash
and then the name of our disk.
In my case, it is disk zero.
Then we're going to hit the Return key.
Now you might be able to see that immediately,
we get some details about the SSD on our Mac.
So here, where it says data units written,
you can see it returns a value of 4.3 terabytes.
That just means that this particular SSD,
over its entire lifespan,
has written exactly 4.34 terabytes.
Same with the Data Units Read,
I've got 8.25 terabytes of total data this SSD has read.
You can also see the percentage used,
the available spare threshold, and the available spare.
Now I'll cover exactly what these mean in a little bit.
But first of all, let's bring up
a third-party tool called DriveDX.
Now DriveDX has a 14-day free trial.
After that, obviously you have to pay for it.
So that's why I showed you Smartmontools using Terminal.
That's free. It'll always be free.
And the second reason I showed that to you
is because we now have these two separate sources
of data that we can now compare
and make sure that they are correct.
And as you can see, on DriveDX,
if we come down into the Health Indicator page here,
our data units written is 4.3 terabytes
and that is the same over here, 4.34 terabytes.
I will also include a link to download DriveDX
in the description if you are interested.
Okay, so now that we know all
of these figures match up and are correct,
let's have a look at what they actually mean.
And for this, I'm actually going
to switch to my M1 MacBook Air.
So this is a base model M1 MacBook Air.
Eight gigs of RAM, 256 gigabyte SSD.
As you can see, we have written quite
a bit more data than on the previous MacBook.
So over the last year of using this particular machine,
I've written 105 terabytes.
Now a quick side note here, guys,
it's important to note that this is not a realistic number.
You should compare what you're seeing on my computer
or for that matter, on other computers
you see from other people
because our usage is always going to be different to yours.
For me, for example, on this machine,
we've been running benchmarks, lots of testing,
writing lots of data to the SSD.
It's been my daily driver for the last year.
So 10 hours a day, watching videos, Photoshop, emails.
We've also done a lot of swap memory testing as well.
So using a lot
of unoptimized non-M1 native apps running on Rosetta 2.
So this 105 terabyte figure is,
you're probably not going to be anywhere near that.
And likewise, with other computers
you might see from other people,
they may only use their computer for an hour a day
or they might use their computer 15 to 20 hours a day.
You never know.
So don't compare to anyone else.
Just look at what your specific computer is telling you.
So let's actually talk about
what these particular figures actually mean.
So starting with the life percentage used,
I'm going to click on this.
And if you guys want to pause the screen right now,
you can give this a read.
And this is going to give you an overview
of what exactly that figure means.
But in layman's terms, if that number reaches about 100,
it means that the SSD is possibly consumed
and it might possibly start to have issues
or have a higher chance of failing.
Doesn't mean that even if you hit 100,
that's going to happen though.
As you guys can see, if you pause the video and read,
you can actually go past that figure of 100.
Even if you go past 100, there's a good chance
the SSD may still work perfectly fine.
It also does not mean that you've used
up 7% of the storage space on your SSD.
And if we come over here to Smartmontools,
we can see the available spare threshold is 99%
and the available spare is 100%.
So for this particular machine that's written
over 100 terabytes in 12 months, that's pretty good.
And if you guys have watched my previous video
on this topic where I go into detail
on just how long SSDs can last,
even these 256 gigabyte SSDs, it's very likely
it's going to hit two petabytes of data rights before it fails.
Two petabytes is obviously 2,000 terabytes which is a lot.
Right now, we're sitting
at 105 terabytes over the last 12 months.
And as you can see,
that's only used up about 7% of the life percentage.
So if we do some quick maths,
so let's assume that once we hit 100
for this life percentage, the SSD is going to fail.
Let's do 100 divided by 7%
that we've already used, and that is 14.2.
So that means I can keep writing 105 terabytes
on this machine every single year for 14.2 years
until this particular number here hits 100,
and I might start to see some issues or the SSD might die.
Okay, so moving back to my new M1 Mac computer
that's only written 4.3 terabytes.
Let's talk about how you can determine
how much data you write every single day.
And this is going to be helpful to estimate
how long your SSD will last with your current usage.
So there's two ways to find out this number.
The first one is download DriveDX or Smartmontools
and find out how much data your SSD has written in total.
And then you want to divide that
by roughly how many days you've owned the computer.
So using my M1 MacBook Air
that's written 105 terabytes as an example,
105 terabytes is 105,000 gigabytes.
If we divide that by 365 days,
that's how many days I've been using that machine for.
That works out to be around 287 gigabytes per day
I was writing to the SSD.
And again, guys, that's worst case scenario.
I was really slamming that SSD for the last 12 months.
So your usage is probably going
to be significantly less than that.
Now the second way to find this out
is actually a little bit more accurate
because obviously your usage will change
from day to day and week to week.
So if I just shut down both of these programs here
and I actually bring up Activity Monitor.
If I come into the Disk tab here,
you can see I have a column here called Bytes Written.
If you don't have that column,
right-click up here where it says Process Name
and make sure that you click or select Bytes Written.
And this is going to tell you how many gigabytes
or megabytes or whatever a particular program has written
to your SSD since your computer has been last turned on.
So for example, Firefox here,
I do a lot of YouTube videos in Firefox.
So I've written 56 gigabytes.
Final Cut Pro also writes a lot to the SSD,
but Final Cut Pro is not coming up right now
because it's currently closed.
If I were to open up that program,
it would show me probably about
a couple of hundred gigabytes here.
So how do you find out how long
your computer has been on since it was last turned off?
It's pretty easy.
Come here to the Apple logo, click About This Mac.
Then you want to click System Report.
And then you want to come to Software.
And down the bottom here, you can see Time since boot.
So about six days and three hours for me.
Now, if we remember that figure and look down here
at the total data written, which is 948 gigabytes,
if we divide 948 divided by six days,
that's an average of about 158 gigabytes per day.
I've written to this SSD over the last six days.
And again, guys, this is a production machine.
We do a lot of benchmarking, a lot of video editing on here.
So that's pretty much worst case scenario.
Again, you are probably going
to be writing significantly less to your SSD.
One thing to note as well, guys,
is this particular figure here where it says Data written,
that includes external drives.
So if you've plugged in an external hard drive
and you've been editing off that hard drive for example,
and your Mac has been writing data to that hard drive,
that's going to be included here as well.
So if you want a truly accurate idea
of just how many gigabytes you write
to your SSD each day, restart your computer,
make sure you don't plug in any external drives,
and then after three days or a week, for example,
come back to Activity Monitor,
check this particular box here where it says Data Written
and just divide that by the number
of days it's been since your Mac was last restarted.
But again, guys, even if you're the type
of person to be writing hundreds
and hundreds of gigabytes per day,
like I mentioned in my previous video,
a lot of these SSDs,
even the small 256 gigabyte-capacity SSDs
can write petabytes and petabytes of data before failing.
So again, going back to my M1 MacBook Air,
105 terabytes per year,
a lot of those 256 gigabyte SSDs could write 345 petabytes,
which is 5,000 terabytes.
So that's going to be a very, very, very long time
of writing that much data per year before that drive fails.
Now there's no guarantees there.
SSDs can still fail at any time
even if they haven't been used much,
but that's extremely rare and I wouldn't worry about it.
Just gives you an idea
of some of the lifespan of these SSDs.
Anyway, guys, any questions, make sure you join the Discord.
I'll link that down below.
But apart from that, thanks for watching this video,
and I'll catch you in the next one.