Apple's SSD milking machine...

[PKTKS]

i will not post specific reviews and dozen rant posts...
Instead... just point the issue for fun...   

If you have not seen latest SSD fiasco (if that can be called fiasco)...
The new  machines have - HALF - speed for half a chip ..
with very same specs...  for just more U$400 tag price...

but U$ 400 for HALF  the specs...
I have not proper insults for that..

google for :   APPLE M1 x M2 SSD slow speeds...
anything like that

Paul

[DiTBho]

Can you use the internal SSD only to load the kernel, everything else is on an external SSD / HD?
This way, you can offer Apple a figured finger, buy the smallest and cheapest SSD, and use the money to buy a decent external drive.

I'm not sure if internal Apple SSDs are compatible with what you can find on the market, but I'm 100% sure that the one used in the Apple Studio line is proprietary, and even if you find two Apple SSDs made for the same Apple Studio model, you can't change it without Apple's permission.

[Kjelt]

Can you use the internal SSD only to load the kernel, everything else is on an external SSD / HD?
This way, you can offer Apple a figured finger, buy the smallest and cheapest SSD, and use the money to buy a decent external drive.

Yes you can but you miss the whole point.
The reason people buy these ludicrous over expensive laptops is because they are thin, lightweight and look sexy while drinking their stylish coffee.
Adding an external drive just destroys that whole look 

But indeed it was a stupid move from Apple, sent all reviewers the fast 1TB version so everyone is enthousiastic and then crippling the 256GB version by not installing two 128GB flash chips but a single 256GB flash chip, reducing access speeds with a factor of almost 2.

[PKTKS]

one more reason...

these snobby dudes boast that overpriced shit as some status cult gizmo 

could never figure that out really

My computers are tools..

Paul

[DiTBho]

Yes you can but you miss the whole point.

I bought an M1 laptop because other Arm laptops simply suck regarding ergonomically, screen quality, and battery.
I bought an M1 laptop because I like neither DaVinci nor Premiere, personally I prefer Finalcut, which runs very well on Apple Silicon.

I want Apple Hardware because it's the best option for what I need, but I don't want to waste money on their proprietary SSDs.

[DiTBho]

thin, lightweight and look sexy while drinking their stylish coffee.

I owned a Lenovo Carbon 2015. Not bad.

Check it out:
- it's thin!
- it's lightweight
- it has a nice keyboard
- it looks sexy when you put it on the table during an hack-meeting.
- it's Windows 10 certified
- it's also Linux-friendly with 97% peripherals really supported
- it comes with the same price of M1, a bit expensive but not so much

So what's wrong with it?  ... Well, it has x86-64 CPU, and the battery only gives you 9 Hours of continuous working.

The M1's one gives you 20 hours!

[coromonadalix]

thin, lightweight and look sexy while drinking their stylish coffee.

I owned a Lenovo Carbon 2015. Not bad.

Check it out:
- it's thin!
- it's lightweight
- it has a nice keyboard
- it looks sexy when you put it on the table during an hack-meeting.
- it's Windows 10 certified
- it's also Linux-friendly with 97% peripherals really supported
- it comes with the same price of M1, a bit expensive but not so much

So what's wrong with it?  ... Well, it has x86-64 CPU, and the battery only gives you 9 Hours of continuous working.

The M1's one gives you 20 hours!

Give me that one   i'm gonna be happy as hell   loll

[free_electron]

have you seen an LG Gram laptop ? talk about light.... and they can be expanded with additional SSD and memory ! has two nVME full length slots and removable DIMM memory
https://www.lg.com/us/laptops



if i ever need a new travelling laptop it'll be one of those.

[DiTBho]

Give me that one   I'm gonna be happy as hell   loll

Would you believe me if I told you I'd be happy to swap my M1 for an optical-KVM-laptop?

Long story, but ... it became my dream laptop (and it's not a laptop), ever since a couple of dudes and a girl with weird colored hair showed it to me at a hack-meeting! 

[bd139]

Oh not that again  . Yay 40 hours of battery life tethered to a fibre link. Just replace it with a mains cable 

As for the apple SSD shit show. That is indeed a shit show. Absolutely no excuse.

As for the other comments in here, I have to wonder if people are just bitter because they are expensive 

They are very much cheaper than the Acorn A420 I bought in 1989.

[thm_w]

I don't know where to find a good reference for price, but, 2x128GB is definitely more expensive than 1x256GB https://www.trendforce.com/price/flash
Of course, more expensive here we are talking about a few dollars, not a significant percentage of the machine cost.
Is this their own flash IC or one they buy?

In total, the M2’s SSD is 34 percent slower than the M1 regarding write speed, with read speed offering a 50 percent difference.
    M1 MacBook Pro: 2900 MB/s (read speed) and 2215 MB/s (write speed)
    M2 MacBook Pro: 1446 MB/s (read speed) and 1463 MB/s (write speed)

Interestingly, this downgrade only seems to be featured in the M2 MacBook Pro with lower storage, with higher storage options offering speeds very similar to the M1, according to YouTuber Aaron Zollo.

The slower speed seems to be related to the fact that the 13-inch MacBook Pro with 256GB of storage only features one NAND flash storage chip, while the previous generation offered two NAND chips with 128GB each.

[bd139]

Those are pretty slow as well. My 14” does 6980MB/s read and 5307MB/s write.

[mariush]

It would make sense in a way to only stock  256 GB and 512 GB flash dies and use them as needed.
If the manufacturing process is good enough, 128 GB chips would not be profitable and such chips would be mostly chips with faulty layers or a lot of disabled memory so they may not get consistent read/write speeds, or the chips would not use all the channels the controller supports..

Maybe they even optimize the controller inside the "chipset" to assume there's always at least 256 GB, that many "channels" in the die, that many "layers" , allowing for better strategies for wear leveling, write caching, ...

[bd139]

Perhaps there are supply problems so they had to cheap it out.

[Kjelt]

It would make sense in a way to only stock  256 GB and 512 GB flash dies and use them as needed. 

They could just place 2 256GB chips and software lock out the extra 256GB.
On the other hand Apple always have these strange memory steps.
Also for the new iPads it is 64GB or 256GB. Nothing in between, and they ask a whopping €160 extra for the difference (half the price of the iPad).

[bd139]

Yeah the 64Gb one is not worth buying either. Very frustrating.

[Someone]

As for the other comments in here, I have to wonder if people are just bitter because they are expensive 

Fake outrage, from a pile of people who never intended to or wanted to buy the product. Some feature/performance is worse on new product, ok, buy the old one if thats important to you? (they are much cheaper right now).

SSD bandwidth scaling with chip flash chip count has been a thing in SSDs for a long time, but but but APPLE!#@%^ WEGJGWESHJ^^ something something.... triggered.

[SilverSolder]

[...]
As for the other comments in here, I have to wonder if people are just bitter because they are expensive 
[...]

Not at all - one of the best Apple products is their shares!

[bd139]

As for the other comments in here, I have to wonder if people are just bitter because they are expensive 

Fake outrage, from a pile of people who never intended to or wanted to buy the product. Some feature/performance is worse on new product, ok, buy the old one if thats important to you? (they are much cheaper right now).

SSD bandwidth scaling with chip flash chip count has been a thing in SSDs for a long time, but but but APPLE!#@%^ WEGJGWESHJ^^ something something.... triggered.

There’s no fake outrage. Particularly in apple specific forums. Lots of people held off on buying the first generation ARM machines and were primed to purchase these. And they are inferior to the first generation machines.

My daughter for example was going to buy an M2 iMac when they come out. Now this is in doubt.

[bd139]

[...]
As for the other comments in here, I have to wonder if people are just bitter because they are expensive 
[...]

Not at all - one of the best Apple products is their shares!

That’s a good thing. You don’t want to invest in a tech company’s products who can’t afford to back them up with capital and interest.

[Someone]

As for the other comments in here, I have to wonder if people are just bitter because they are expensive 

Fake outrage, from a pile of people who never intended to or wanted to buy the product. Some feature/performance is worse on new product, ok, buy the old one if thats important to you? (they are much cheaper right now).

SSD bandwidth scaling with chip flash chip count has been a thing in SSDs for a long time, but but but APPLE!#@%^ WEGJGWESHJ^^ something something.... triggered.

There’s no fake outrage. Particularly in apple specific forums. Lots of people held off on buying the first generation ARM machines and were primed to purchase these. And they are inferior to the first generation machines.

My daughter for example was going to buy an M2 iMac when they come out. Now this is in doubt.

Sounds like you are in that group! What particular task is completely ruined by having a slower throughput SSD? (if buying the new one) or conversely, what task is ruined by having a slightly slower processor? (if buying the old one) Computers are way off into imaginary performance for the majority of users, disk throughput of that magnitude is way down on the things that impact performance for the vast majority of people (thinking 99.999% here), and if that really was the killer limit just buy the older one, or not the absolute smallest storage SKU.....  so many ways to avoid this imagined "dealbreaker" of yours. You're just adding to the FUD with more of the nonsense:

"I WANT EVERYTHING BETTER AND CHEAPER AND WONT BUY ANYTHING LESS", ok... don't buy it if it offends you so much? why the need to broadcast this ridiculously individual corner case detail to the world? It isn't some mandatory purchase, the choice is yours, if the value proposition isn't there then just move on.

Forums are full of people big on talk and shy on actually doing, "apple specific" forums are just the same as seen on here with people endlessly discussing test equipment they were never in the market to buy.

[bd139]

Sounds like you are in that group! What particular task is completely ruined by having a slower throughput SSD? (if buying the new one) or conversely, what task is ruined by having a slightly slower processor? (if buying the old one) Computers are way off into imaginary performance for the majority of users, disk throughput of that magnitude is way down on the things that impact performance for the vast majority of people (thinking 99.999% here), and if that really was the killer limit just buy the older one, or not the absolute smallest storage SKU.....  so many ways to avoid this imagined "dealbreaker" of yours. You're just adding to the FUD with more of the nonsense:

"I WANT EVERYTHING BETTER AND CHEAPER AND WONT BUY ANYTHING LESS", ok... don't buy it if it offends you so much? why the need to broadcast this ridiculously individual corner case detail to the world? It isn't some mandatory purchase, the choice is yours, if the value proposition isn't there then just move on.

Forums are full of people big on talk and shy on actually doing, "apple specific" forums are just the same as seen on here with people endlessly discussing test equipment they were never in the market to buy.

Well unlike a lot of people, we aren't buying these machines to have a wank over. They really do get the shit hammered out of them doing actual real work. In my case I'm running a full stack of compilers on it and doing RAW photo editing and 4k video editing on a regular basis. All of that is very SSD and CPU intensive.

If you compare turnarounds on my current compiler workload you will see what I mean:

Ryzen 3700X desktop: 54s
MacBook Air M1: 23s
MacBook Pro M1 Pro: 15s

Now do that 200 times a day and you see where it adds up when I get paid to complete jobs in set time windows.

In the case of the M2, a lot of people will be buying them for the video and image workflows because they are the most affordable pro-line portable computers out there which run the Apple platform specific tools that people want to run. Like Final Cut Pro etc. If you are currently running an M1 and you want that 20% gain and you buy a M2 and find it's not there then you're going to be pissed.

The point is if you get pissed now, it makes people aware of it, negatively affects sales at Apple and they will never make that mistake again. This leads to excellent priced and performance entry level machines, unlike the whole fucking PC market which is a shit show because there's such a diversity of trash and no way to get traction against it.

[Someone]

They really do get the shit hammered out of them doing actual real work. In my case I'm running a full stack of compilers on it and doing RAW photo editing and 4k video editing on a regular basis. All of that is very SSD and CPU intensive.

Its a 256GB SSD, that's not going to hold much more than 10's of seconds if the 1500MB/s vs 3000MB/s speed is "limiting". You're off in bullshit world. The task based testing for photo editing was AN ENORMOUS 15% SLOWER, STOP THE PRESSES!
https://www.macrumors.com/2022/06/27/m2-macbook-pro-256gb-ssd-real-world-tests/
If that sort of minor reduction in speed is an issue, pay up and get more storage and performance?

Now do that 200 times a day and you see where it adds up when I get paid to complete jobs in set time windows.

If the older model is faster, and time is important, you know, buy the older (cheaper and faster) model and profit?? or just get the extra storage.

You are exactly all talk chasing imaginary unicorns and blowing up a non issue into something it isn't, your use case is imaginary (smallest storage but demanding high throughput). Trivial to avoid the minor issue, but you keep justifying why it needs so much "airtime". Keep feeding the nonsense mill and I'll keep pointing out how you're just drumming up hating.

[bd139]

You picked the photo editing as a case where I specified 4k video...

I bought the M1 MacBook Pro so you are correct - I optimised for performance.

You're the one with the outrage 

[Someone]

You picked the photo editing as a case where I specified 4k video...

Lets see....

doing RAW photo editing and 4k video editing

You said photo editing and video editing. Do you have some example benchmarks or workloads in video that are impacted by that reduced throughput? They aren't going to be significant when video processing is usually GPU/CPU bound, disk bound video was a thing before 1000MB/s drives, 1500MB/s vs 3000MB/s isn't going to make significant differences. But you say its some problem (of your imagination).

[bd139]

No, it's really not my imagination. That's your assumption and your argument.

I shoot 4k 60fps video from DLSR and iPhone and work with 3-5 streams (mix RAW and ProRes). That will be fine on an M1 MacBook Air. On a MacBook M2, nope. It's not about aggregate bandwidth either - each stream has to seek blocks and if you hit swap when you are working you need overhead for that.

My old MacBook Pro, an Intel one was slightly better than the M2 measured performance and it was hitting an IO wall regularly.

Edit: also surely you see the irony of complaining about people complaining about something by creating a tangent on a thread about it. Shock-ception! I have better things to do so that was my last comment on the matter

[DiTBho]

it's the second time I think these topics are getting more frustrating than Apple products, which is depressing.

(so you can guess why I am more enthusiast for an home-made optic-Kvm than for that usual big *hits.)

Anyway, I am going to return my Apple Studio to Amazon! I mean, I need a similar machine, but I like neither its SSD nor the Apple crazy policy.

[bd139]

Indeed. It's just fake meta-outrage.

I don't really care. It's a toaster to me. Buy it, use it until AppleCare runs out then lose it before I incur any risk. If I don't like it to start with I return it like you're doing.

tco = (initial_cost + apple_care - sale_cost) / months_apple_care

£32 a month for a studio. I'm thinking about it. That's couch change.

Edit: although I might just blow that on a spectrum analyser instead at the moment...

[SilverSolder]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

[bd139]

It's fine for most edits I do which are usually < 10 minutes total. Once I'm happy I render it out and nuke the source media as I don't need it. I archive stuff on a 1TB external disk which is rendered and push it to Amazon S3 for backup.

I've got a 512Gb SSD in my 14" MBP and that's sitting at 351Gb free. That contains everything I've ever done as well as the OS and apps.

Only people editing long ass YT crap and films need 1TB or more (or those with a serious data hoarding problem)

[Someone]

No, it's really not my imagination. That's your assumption and your argument.

I shoot 4k 60fps video from DLSR and iPhone and work with 3-5 streams (mix RAW and ProRes). That will be fine on an M1 MacBook Air. On a MacBook M2, nope. It's not about aggregate bandwidth either - each stream has to seek blocks and if you hit swap when you are working you need overhead for that.

So you'd have some benchmarks to back that up? (against a computer you don't own and don't want to buy) 

Below is one of the "slow" M2 256GB benchmarks on throughput (with results for equivalent prores and compressed raw data rates) boo hoo hoo, only 400 frames per second of 4k prores. Without going to the obvious solution of proxies you'd need to have more than 5 simultaneous 60fps streams to start worrying, which would....  be less than 4 minutes of storage if it filled the entire drive. Its not realistic, real people would just drop to proxies as you're not editing anything of such value (Hollywood movie etc) in that limited space that you need exact pixel playback in realtime.

You picked the applications, and they aren't significantly impacted. Compiling/software is often IO request rate limited more than throughput, I've done those benchmarks on projects when selecting workstations. Throughput above 1000MB/s is limiting almost nothing.

[Someone]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

Or more likely, some external drives on the the thunderbolt port(s). Still, the point is pretty simple that high throughput on a small sized drive is useless beyond some contrived examples. Reading through the entire data of the drive in under 3 minutes is not a real world use case.

[bd139]

Meh your funeral. Measurable difference here outside synthetic benchmarks which you tell me isn't possible and that I'm stupid. All your "evidence" is sourced from a screenshot and some outrage.

And if you read the thread further back I did want to buy an iMac shaped version of it for my daughter.

Yeah great argument. I'm done. Not getting into another one of these fucking threads again. Life's too short.

[Someone]

Meh your funeral. Measurable difference here outside synthetic benchmarks which you tell me isn't possible and that I'm stupid. All your "evidence" is sourced from a screenshot and some outrage.

Measurable difference of what between M1 256GB and M2 256GB units? You have some measure of this you won't share? The example you did share of 3 different computers doing some task has very little to do with their SSD throughput when the all the other variables are a) not stated and b) likey all over the place, and c) the task isn't stressing/challenging throughput.

If there were real world differences, why aren't people posting examples of it? You say you know the truth but can't substantiate it, given the easily found evidence to the contrary your argument is looking full of holes.

[bd139]

Code: [Select]

bd139 ~$ unsubscribe-topic


[mariush]

The endurance of that 256 GB of flash memory is probably around 100-150 TB

I'd be a bit worried about editing with such low amount, due to writes.  For a 10 minute video you could have 30-50 GB of content, and you'd render another 5-10 GB ... so 10-20 youtube videos could potentially burn through 1% of your SSDs endurance, and then you'd have to pay for new memory chips.

[bd139]

No it’s not. It’s 1Pb+ these days.

I’ve written 900TB on consumer SSDs.

[Monkeh]

100-150TB is probably reasonable for the very low end of the market - which is a valid section of the market. It's just not on the same page of the atlas as Apple.

[bd139]

I dunno. We burned up ass end crucial and sandisk ones to see what would happen and it was very uneventful 

Best one was the hitachi enterprise PCIe 6.4TB one. Those do 30PB a go in database servers. But not cheap.

[wraper]

But indeed it was a stupid move from Apple, sent all reviewers the fast 1TB version so everyone is enthousiastic and then crippling the 256GB version by not installing two 128GB flash chips but a single 256GB flash chip, reducing access speeds with a factor of almost 2.

Actually for SSD, it's industry normal that drives of the same model line have worse performance for smaller size. Same controller, same NAND chips but lower count. And thus situation may easily be that same size of newer generation SSD have worse performance than previous since it uses newer generation of NAND of larger size but less channels are used for the same size models.
To PKTKS
Why do you compare M2 prices with different SSD size? AFAIK performance is worse only for M2 with 256GB SSD when compared to M1 with the same SSD size.

[bd139]

On the M2 my objection is by the time you buy the 512Gb one it’s £1549. You can get a 14” MacBook Pro with more cores, more SoC bandwidth, more ports, twice as much ram, 4.5x the read/write performance and an XDR screen for less than £200 more on Amazon 

[Cerebus]

Code: [Select]

bd139 ~$ unsubscribe-topic


So, you have got a nice warm redhead waiting! 

[bd139]

Fortunately no 

I’m only replying to this as I’m being internally murdered by an Asda burrito.

[Monkeh]

I dunno. We burned up ass end crucial and sandisk ones to see what would happen and it was very uneventful 

Best one was the hitachi enterprise PCIe 6.4TB one. Those do 30PB a go in database servers. But not cheap.

Try some WD Greens for some proper ass-end. About as bad as you can get commercially unless you're PKTKS and buy Aliexpress specials. And yet, they still are fine for basic tasks to replace spin-stabilised data storage..

[wraper]

After a bit of thought, the reason they used a newer generation of NAND instead 2x of older one may be not money skimping at all. M2 will be produced for longer and as NAND manufacturers like to phase out production of their older NAND and mostly produce latest generation, they may need to move to newer NAND in future production of M2. And then it would be a real scandal if they at some point nerfed performance of 256GB M2. EDIT: also clinging to old NAND during chip shortage is not the best idea FWIF.

[mariush]

The amount of writes you can do on a SSD varies depending on type ... SLC, MLC, TLC , QLC from best to worse.
Very few SSDs are still MLC, majority of drives these days are either TLC or QLC

Examples of TLC drive

WD SN570 (I think it's 112 layer TLC memory chips) : https://cdn.cnetcontent.com/syndication/feeds/wd/inline-content/C2/2D253893B5A85CE8F7AAFA3C5D3B0CF3E5D96C5B_PRODUCTBRIEFWDBLUESN570NVMESSD_source.PDF

Note it's 150 TBW for the 250 GB model,  300 TBW for the 500 GB model and 600 TB for the 1 TB model.

Same ratings for the  WD SN550, here's datasheet (which uses 96 layer TLC memory if my memory is correct) :  https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal-drives/wd-blue-nvme-ssd/data-sheet-wd-blue-sn550-nvme-ssd-idk.pdf

The 112 layer memory is technically a bit worse, but they stretch the amount of writes by using bigger amount of write cache and a newer better controller - they switch some amount of TLC memory to pseudo-SLC mode.

Samsung 980 uses the latest TLC Samsung makes, also has 160/300/600 TB rating : https://semiconductor.samsung.com/resources/data-sheet/Samsung_NVMe_SSD_980_Data_Sheet_Rev.1.1.pdf

Samsung 980 has one of the biggest write caches, if there's enough free space it has up to around 60 GB of pseudo-SLC write cache (for the 1 TB model) ...

QLC memory is much worse .. ex Kingston NV1 drives are rated 240 TB for the 1 TB model, Samsung QVO drives are rated at around 360 TB for the same 1 TB model.

Sure, yes, you can actually write more than these estimated amounts, but some blocks of memory will wear out and the SSD will degrade.


And as for the M1 apple machines... thread reminded me of this, not sure if it was fixed or not : https://twitter.com/marcan42/status/1494213855387734019?lang=en





Quoting from the thread

Hector Martin
@marcan42
Well, this is unfortunate. It turns out Apple's custom NVMe drives are amazingly fast - if you don't care about data integrity.

If you do, they drop down to HDD performance. Thread.
9:35 AM · Feb 17, 2022·Twitter Web App

For a while, we've noticed that random write performance with fsync (data integrity) on Asahi Linux (and also on Linux on T2 Macs) was terrible. As in 46 IOPS terrible. That's slower than many modern HDDs.

We thought we were missing something, since this didn't happen on macOS.

As it turns out, macOS cheats. On Linux, fsync() will both flush writes to the drive, and ask it to flush its write cache to stable storage.

But on macOS, fsync() only flushes writes to the drive. Instead, they provide an F_FULLSYNC operation to do what fsync() does on Linux.

So effectively macOS cheats on benchmarks; fio on macOS does not give numbers comparable to Linux, and databases and other applications requiring data integrity on macOS need to special case it and use F_FULLSYNC.

How bad is it if you use F_FULLSYNC? It's bad.

Single threaded, simple Python file rewrite test:

Macbook Air M1 (macOS):
- flushing: 46 IOPS
- not: 40000 IOPS

x86 iMac + WD SN550 1TB NVMe (Linux):
- flushing: 2000 IOPS
- not: 20000 IOPS

x86 laptop + Samsung SSD 860 EVO 500GB SATA:
- flushing: 143 IOPS
- not: 5000 IOPS

So, effectively, Apple's drive is faster than all the others without cache flushes, but it is more than 3 times slower than a lowly SATA SSD at flushing its cache. Even if all you wrote is a couple of sectors. You pay a huge flush penalty if you do *any* writes.

Here, "flushing" on macOS means F_FULLSYNC and "not" means fsync(); on Linux both are fsync(), but "not flushing" is measured by telling Linux that the drive write cache is write-through (which stops it from issuing cache flushes).

Note that the numbers are filesystem-dependent (and encryption makes things more complicated); e.g. the SATA SSD numbers double on VFAT vs. my root filesystem (ext4 on LVM on dm-crypt), but the pattern is clear.

macOS doesn't even seem to try to proactively issue syncs; you can write a file on macOS, fsync() it, wait 5 seconds, issue a hard reboot (e.g. via USB-PD command), and the data is gone. That's pretty bad.

Of course, in normal usage, this is basically never an issue on laptops; given the right software hooks, they should never run out of power before the OS has a chance to issue a disk flush command. But it certainly is for desktops. And it's a bit fragile re: panics and such.

Unfortunately, this manifests itself as quite visible issues on Linux. For example, apt-get on Asahi Linux is noticeably slow. Making fsync() not really flush on macOS is not fair; lots of portable software is written to assume fsync() means your data is safe.

Our current thinking is we're going to add a knob to the NVMe driver to defer flush requests up to a maximum time of e.g. 1 second. That would ensure that a hard shutdown never loses you more than 1 second of data, which is better than what macOS can claim right now.

Alas, that's still not quite safe. Not flushing means we cannot guarantee ordering of writes, which means you could end up with actual data corruption in e.g. a database, not just data loss. There's no good way around this other than doing full flushes.

So the unfortunate conclusion is that if you're e.g. running a transactional database on Apple hardware, and you need to be able to survive a hard poweroff without data corruption, you're never going to get more than ~46 TPS.

Unless Apple improves their ANS firmware to fix this.

And for what it's worth, I inadvertently triggered a data consistency issue in macOS while testing this. Before running any tests I had GarageBand open. I closed it without saving the open project. After the first hard reboot later, it tried to reopen it and threw up an error.

So I guess the unsaved project file got (partially?) deleted, but not the state that tells it to reopen the currently open file on startup.

Data consistency matters.

[Monkeh]

Note it's 150 TBW for the 250 GB model,  300 TBW for the 500 GB model and 600 TB for the 1 TB model.

Bearing in mind these are numbers for warranty purposes, which makes them highly conservative.

[bd139]

Oh not the flush thing again.

1. Consistency is guaranteed.
2. Currency of data is not.
3. Computer has battery.
4. It’s a client computer not a server.

It’s perfect trade off for workstation and desktop use. 

[Bassman59]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

Everyone I know who does video and audio edition keeps the assets on external drives.

[SilverSolder]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

Everyone I know who does video and audio edition keeps the assets on external drives.

Not while editing, surely? - you'd want max disk access speed for that?

[Someone]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

Everyone I know who does video and audio edition keeps the assets on external drives.

Not while editing, surely? - you'd want max disk access speed for that?

Hence why fast external drives have been a thing for a long time, and you can distribute the sources across the drives to multiply their bandwidth (and storage). SCSI, firewire, now thunderbolt, all exceeded the speed of the practical storage at the time.

[free_electron]

Not while editing, surely? - you'd want max disk access speed for that?

they use proxy files ( lower resolution ) for all the rough work. once they are ready to do the fine tuning they use fast arrays over thunderbolt.

[Bassman59]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

Everyone I know who does video and audio edition keeps the assets on external drives.

Not while editing, surely? - you'd want max disk access speed for that?

Yes, while editing.

[SilverSolder]

Is 256GB enough for video editing anyway?  -  Wouldn't you want 1TB or better?

Everyone I know who does video and audio edition keeps the assets on external drives.

Not while editing, surely? - you'd want max disk access speed for that?

Yes, while editing.

So it boils down to how large are the projects you typically work on?  -  I don't seem to have any difficulty using hundreds of gigs while editing video even at 1080p....