MacBook Air, M2 Chip, 8GB RAM: Nothing is open, but half the memory is gone | Hacker News Reader

MacBook Air, M2 Chip, 8GB RAM: Nothing is open, but half the memory is gone

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50 pointslopkeny12ko91 comments

I have this exact build of MacBook Air and in day to day use browsing the web, doing some light coding, and connecting to Kubernetes clusters hosted in the cloud, I don't really notice. There is definitely some disk swapping occurring but you don't really notice it in small amounts due to how fast the SSDs are.

Would I recommend the 8GB of RAM to someone who wants to use it as their primary development machine or for heavy photo editing, absolutely not. Would I say it's OK for casual use, yes.

Do I think Apple is being stingy considering their incremental cost for an extra 4GB or 8GB of RAM in the base model would be tiny, yes.

I thought this as well and bought my wife the 8GB model, thinking it would be enough for her casual use. With nothing open but Chrome or Safari (dozens of tabs, sure) it will lock up and sometimes even hard restart. 8GB is just not enough for anyone anymore.

I'd strongly consider returning the machine. This is very far from my normal experience with an 8GB M1 over several years (as a developer as well as a casual user).

Either there’s something much bigger running or the hardware is defective. I used an 8GB M1 with VSC, Podman, Slack, etc. for a few years during the pandemic and it was fine. Chrome is a notorious memory hog but even then it was okay so I’d review the installed extensions if it’s that high.

Is it swapping to disc, or compressing the memory?

If someone's primary use case is heavy media editing, I wouldn't recommend an Air in the first place. It has its uses for casual people and coders who primarily work in the cloud, but let's not pretend that it is a high end business level laptop.

We have bought 200+ macbook pro’s over the years, but when the M3 air came out we started rolling that out to everyone including developers and it has been a huge success. I would only recommend Pro’s for heavy media editing applications right now. We don’t do any AI/ML stuff yet so not sure how that will change the landscape.

I use an Air for ML. It's perfect if you work in the cloud. Locally it's too much hassle. Not just because of the limited power, but because of lack of support for MPS in recent kernels in modern frameworks.

I use a 2023 MacBook Air with 24GB memory, and I can’t tell the difference to a MacBook Pro.

Integrated memory on Apple Silicon has made the trade-offs much simpler to understand because there’s no separate GPU and VRAM to think about. The performance difference between Air and Pro models is so small, it’s irrelevant for practically anything.

I have used both. Air and Pro. For working remotely in the cloud on ML, nothing beats the Air. For nearly everything that runs locally and goes above light coding (e.g. modern web dev with endless node modules), the Pro is significantly better.

I have sadly to use one M1 with 8gb and it is really painful.

I think that a normal user will feel the bad effect of the low ram amount but will not really realize where the problem is coming from.

Switching from one app to another is painfully slow. It might take 1, 2 or more seconds to go from one app to another in my opinion.

The os is really greedily evicting app memory once you switch to another window. And reload it when you come back.

I even have the personal hypothesis that Apple is keeping as-is the ergonomically awful Dock because of that. As it is difficult to switch between multiple windows of a single app, you can't easily realize how show you pass from a window to another. Like a magic trick.

> As it is difficult to switch between multiple windows of a single app

Magic trick: press command + ~ to quickly switch to another window of the same app.

Wizard trick: map this to four finger trackpad force press (via BetterTouchTool)

> I have sadly to use one M1 with 8gb and it is really painful.

I've been using an 8GB M1 for a couple of years, including for development with C#, Go, Python, and Rails. I've had triple-figures of browser tabs open, Office 2019 Mac, Affinity Designer, and more all running at once. And never in all those years have I experienced sluggishness or slowdown either in-app or during switching.

I don't doubt your experience, this is simply to say that not all observed behaviours can be assumed to be generally applicable.

that's crazy to me. I was given a 32GB MBP for work and found it to constantly eat all of the ram and slow down to the point of being useless and require restarts every few days. It took considerable active management to keep more than 4GB free. I upgraded to a higher ram machine now and all of my challenges went away.

My main workflows are python dev and data analysis, some CAD modeling with fusion, and inevitably keeping too many chrome tabs open. Still, with what seemed normal to me, 32 GB didn't cut it, but reading these discussions is crazy making since I seem to be the only one.

> It took considerable active management to keep more than 4GB free.

This illustrates ignorance of the basics of how memory management works on macOS (e.g., "free" memory is not a determination of whether you need more RAM) https://support.apple.com/guide/activity-monitor/check-if-yo....

I'm 90% sure your workplace supplied malware ala cloudstrike is causing this.

I bought my gf an M3 pro with 8gb ram and text input in the browser is often slow as hell (Google Docs, Facebook Messenger, etc.). Takes a moment before a character appears after typing it. I've never owned a Mac myself so I believed Apple's marketing speak about 8gb being the 16gb on their platform (not to mention that the 16gb upgrade is ridiculously expensive) but boy are they wrong. Maybe in native applications their memory magic works but definitely not in a browser. She does some light React dev and it's been fine for that though (but not mind-blowing).

It's strange how much people's experiences vary. I'm typing this on an M2 with 8GB and browsing in Chrome works totally fine.

I wonder if it's due to extensions or something like that? Or could it be due to browsing different websites or using different networks?

Could be, but I got the same results in incognito mode.

What about with Safari?

Yeah it sucks. I use an M1 8GB for work because at work we're not allowed to order CTO models :( We have to order through a reseller that refused to do this. It's very tough to work with (though I'm sure part of the reason is Microsoft's incompetence, their apps perform very poorly and a lot of them are electron crap now).

Apple saying the "our 8GB is equivalent to 16GB" is something they've always done. Even in the PowerPC days they were selling the "megaherz myth" as if their megahertzes were better than intel's.

Of course when they moved to intel Macs received a huge performance boost...

This isn't enough information to determine if it's a memory related issue. Have you verified this using the memory pressure graph in Activity Monitor? https://support.apple.com/guide/activity-monitor/check-if-yo...

The real problem is that the default option is the one with mass distribution and if you want it on sale or discounted or on release day, it’s the one you are probably going to end up with that most users have. It’s not only the way you get soaked on the upgrade but the way most users have these low specced devices.

It's more than stingy. It's a calculated bet to make the base model suck so more people will buy the extra memory at Apple's hugely inflated pricing.

For light uses maybe even a low cost windows machine would do. No point buying apple.

There's never a 'point' buying Apple regardless of light/heavy use. You buy Apple if you think it's the best OS/hardware combo, you don't if you prefer otherwise.

Even light use will benefit from long battery life, nice screens, and quality construction, and a low cost windows machine will not have that. You can get a good windows machine with comparable hardware, but then it's not low cost anymore.

Apparently, with the unified memory, Apple has taken the approach that unused RAM is useless RAM. Therefore, the system is greedy at allocating RAM and will release it to higher priority processes as they request it. Your system at baseline will always use "a lot" of RAM. This is to be expected.

So why does the picture show ~1/2GB of swap in use?

MacOS is a bit enthusiastic about swap (and memory compression) and won’t necessarily take stuff out of swap before it is actually needed. That’s why you can have both available RAM and non-zero swap use.

>Therefore, the system is greedy at allocating RAM and will release it to higher priority processes as they request it.

Can this be substantiated? "the system is greedy at allocating RAM and will release it to higher priority processes as they request it" is cold comfort to someone with 10 chrome tabs open and the system freezing up as a result.

> Can this be substantiated?

Sort of. Use the `memory_pressure` CLI tool. You can use it to just simulate a critical memory warning and you’ll immediately see the system free up a lot of RAM.

In macOS parlance the key metric is “memory pressure”. From the tweet’s screenshot you can see memory pressure is only about 20%.

>In macOS parlance the key metric is “memory pressure”. From the tweet’s screenshot you can see memory pressure is only about 20%.

I searched around[1][2] and it's unclear how the chart is actually derived. It should therefore be treated with suspicion, along with other opaquely defined metrics like wework's "community EBITDA".

[1] https://apple.stackexchange.com/questions/202744/what-is-mem...

[2] https://web.archive.org/web/20200415041837/https://support.a...

Eh this feels like a false comparison. Memory pressure is an internal macOS system metric not some public facing self aggrandizing metric. It’s not like Apple has marketing material like “idles at 20% memory pressure!”. I’m sure it’s explicitly and deterministically defined somewhere at least.

> Memory pressure is an internal macOS system metric

Interesting. That'll probably mean it's in the source code Apple publishes for macOS:

https://github.com/apple-oss-distributions/distribution-macO...

Doing a search for the phrase "memory pressure" in the containing organisation (apple-oss-distributions) shows some relevant stuff:

https://github.com/search?q=org%3Aapple-oss-distributions+%2...

• memorystatus.md : https://github.com/apple-oss-distributions/xnu/blob/94d3b452...

    # Memorystatus Subsystem

    Dealing with memory pressure by forcibly recovering pages.
    (etc)

• memory_pressure.1 : https://github.com/apple-oss-distributions/system_cmds/blob/...

    Looks like the man page for a `memory_pressure` command

• freezer.md : https://github.com/apple-oss-distributions/xnu/blob/94d3b452...

    # Freezer

    Details of how some processes can be swapped out to disk.

    [...] The freezer is a limited form of swap on embedded. Under memory pressure,
    the freezer picks apps to freeze.
    (etc)

And a whole bunch more. With some digging, it should be possible to find the exact info. :)

Whoa great sleuthing! Also fun to see Apple internal documentation in .md format

That is a sensible approach, to be honest. RAM is there to be used, not to increase the stats when the computer is idle. Doesn’t Windows do more or less the same thing? I know my Linux workstation is caching a lot of stuff in the available memory as well.

>Doesn’t Windows do more or less the same thing?

Yes, since at least Windows Vista it's been very aggressive about caching into free RAM. It isn't complained about that often because Windows counts that RAM as "standby" RAM together with free RAM.

If you check the screenshot, you'll clearly see that "cached files" is reported separately and doesn't count towards "memory used".

>doesn't count towards "memory used".

Where does it indicate that?

1. there's a notch to the right of "memory used", indicating that what's to the right of it makes up "memory used"

2. "app memory", "wired memory", and "cached files" added together exceeds "memory used", suggesting that not all of them can make up "used memory".

3. apple's own docs: https://web.archive.org/web/20200415041837/https://support.a...

For 1 and 2, "cached" could refer to a portion of app and/or wired memory used that is available to be reused. It's not clear from the screenshot what cached means.

3 isn't in the screenshot, but does vaguely imply cached and app memory are different. It doesn't directly say whether cached is counted in memory used though.

The linked "for more information" makes it less clear. For example, how does purgeable memory fit into the "app memory" "wired memory" and "cached files" distinction?

In another post you mention having ten tabs opening and the system freezing. If that's happening, there's probably a memory issue. I'm not sure Mac's resource monitor showing ~half your memory "used" means there is a problem.

>The linked "for more information" makes it less clear. For example, how does purgeable memory fit into the "app memory" "wired memory" and "cached files" distinction?

I'm not sure what exactly you mean by "purgeable memory", because it hasn't been referenced earlier in this comment chain, and it's not in the OP either. My guess is that of the things listed, only "cached files" can be quickly freed if more memory is needed. You can technically "purge" app memory by compressing/swaping out to disk, but that's much more expensive.

From your link,

>For more information about memory management, refer to the Apple Developer website.

http://developer.apple.com/library/mac/documentation/Perform...

Eager caching is an OS feature, not a RAM feature.

It isn’t gone, it’s used. There may be a problem, but this data point IMO doesn’t provide any evidence for that.

One way to do better is to launch a program that uses lots of RAM, and measure by how much that slows down other processes, whether it makes the Ui stutter, etc.

People are never going to understand RAM, but once more, for the cheap seats:

It’s not gone! It’s there! You’re using it to type this and it will be there for you when you need it again.

>It’s not gone! It’s there! You’re using it to type this and it will be there for you when you need it again.

It's "gone" in the sense that it's not available for other useful stuff. If you bought a system with 16 GB of ram, and the system just decided to eat 15GB of that for its own opaque purposes, leaving 1GB for your workloads, you'd be pretty miffed as well.

    It's "gone" in the sense that it's not available for other useful stuff.

It is and this is the thing that people -- even software engineers -- usually misunderstand.

Evicting cached data is for all intents and purposes a zero cost operation. That's why modern operating systems cache aggressively when they're not busy doing anything else: there's really no downside. If I'm caching file xyz.dll, and it turns out xyz.dll isn't needed, it's not like I have to write it back to disk or do any other (significant) work to evict it from the cache.

So yes: that memory is available, at no additional cost, for any reasonable definition of "available" and "no additional cost."

Honestly, why do so many just assume that the core OS kernel devs at multiple zillion-dollar companies get this fundamental Operating Systems 101 thing so spectacularly wrong in modern OSs?

Guy has 34k karma. He’s one of us. Still doesn’t get RAM.

RAM will never be understood.

> Guy has 34k karma. He’s one of us.

Us vs. them based on 'karma' gives me bad vibes. If anything the fact that 'high-karma' users don't grasp low-level operating systems mechanics is a tell-tale sign of what it takes to get high up in the karma ladder. Better to keep that karma for what it is - a semi-functional means to keep out the trolls - and focus on the message instead of the messenger.

I mean he hangs out here a lot.

>It’s not gone! It’s there!

The sheer prevalence of memory leaks means that is a lie more often than not.

My understanding is that processes generally don't give back memory until it's actually needed, so looking at memory usage in a low-usage state is often misleading. The real test is whether memory is quickly available when requested.

>My understanding is that processes generally don't give back memory until it's actually needed

No, programs that release memory when there's high memory pressure is the exception, not the rule. You'd have to specifically go out of your way to code that in. A basic program that allocates some memory, and then frees it is going to cause the system memory usage to drop immediately.

This person is making a logical error. Their computer was running slow, so they freed up all the RAM they could. The computer immediately saw all that unused RAM, and filled it with temporary cache from the SSD, as computers do. It speeds up future reads and can be dropped immediately if needed for something else. Now he's taking that as evidence that the computer was wasting RAM the entire time, causing the slowness. To do it right he needs to open ram-hungry chrome tabs until the computer gives up all the RAM it can and screams for mercy, then subtract that amount from 8GB. That will give you the actual amount the system wont give up.

This is essentially the same as my 8GB Surface Pro X. Lack of RAM is definitely felt. It's OK for basic web browsing and tasks like word processing but it's not hard to tank.

Computers use RAM and Water is wet.

Sorry, not seeing the issue here - RAM is designed to be used. Why would it flush it if there’s no pressure?

If one gets high swap then that’s a problem, but until then it’s simply the OS preemptively caching because “why not?”.

If you’ve paid for 8GB then you’d expect the OS to use it. Not sure why anyone would want the OS to purge memory when it doesn’t need to. It costs nothing to keep it ready and the OS can either page it out or get rid of it as and when needed.

This isn’t just Macs - happens on Windows as well.

https://www.reddit.com/r/Windows10/comments/11zp2ao/high_ram...

Is water wet?

"Most scientists define wetness as a liquid's ability to maintain contact with a solid surface, meaning that water itself is not wet, but can make other sensation. But if you define wet as 'made of liquid or moisture', as some do, then water and all other liquids can be considered wet."

>Sorry, not seeing the issue here - RAM is designed to be used. Why would it flush it if there’s no pressure?

What indication is there that it could be flushed? The OP is referring to the 4.71GB used figure specifically. "Cached files" clearly can't possibly count towards that, because if you try to add that and the usages to the right (ie. app/wired/compressed) memory, you'll go above 4.71GB. Of items in the rightmost column, which can be "flushed"? All of them look pretty important. Does "flush" mean "swap to disk" for you?

The comments on this thread illustrate an epidemic of ignorance of basic knowledge of macOS memory management (e.g., doing the laymen's mistake of looking at how much memory is used by applications, which is not a useful metric). At the very least you should read this article and note that this is from over a decade ago when memory management on macOS was comparatively simple https://www.mikeash.com/pyblog/friday-qa-2009-06-19-mac-os-x...

If you're not OS engineer with a specific specialization in memory management, I'd suggest just sticking to the Apple article on this subject, which explains the easy way of evaluating whether you're experiencing memory-related slow downs https://support.apple.com/guide/activity-monitor/check-if-yo...

Despite all the Ui tricks and metrics handwaving, even 16GB is not enough for a fluent dev-environment, with an IDE, a browser, slack, teams and docker. My 6 years old xps 13 with 16GB ram and Linux feels as slow as mbp m1 with 16 gb.

8gb is a slap in the face.

Apple's irresponsible sales of unupgradable 8GB ram 256GB storage laptops have lead to plenty of work for consumer tech support. It's just kind of sad seeing the same thing over and over.

"I can't open $x because I'm out of memory." and "Time machine won't back-up anymore." (because their internal storage is full and isn't enough to generate the back-up to send to the octopus of external drives they have to use). And of course the inevitable breaking of the fragile externals and loss of data.

I use a mac with 8gb of ram for professional development — I use it in intensive ways with at least 15 windows open, many of them electron processes. With the notable exception that I must restart my computer about once a week, the system performs flawlessly. 8gb of RAM is fine, and I am not[0] an Apple fanboy. I'd be more angry if I was on the pro model and still only getting 8gb, but that would just be anger out of the principle of it.

Edit: currently I have 20 browser tabs, 3 vscode windows, 2 development servers (and services like postgres and colima to support them) postico 2, spotify, slack, discord, mail, messages, calendar, and a handful of background apps like shottr, raycast, rcmd, rectangle and lunar open. The computer isn't even hot. Its swapping aggressively I'm sure, but its not noticeable.

[0]: https://boehs.org/node/private-apis

Do you use Docker? I had a 16gb Mac a while ago and I had to debug half our code on a metered EC2 because my Docker VM would OOM every time I tried running it, even with everything else closed.

When I hear the "professional development on 8gb Mac" line I typically imagine SaaS webdev or Swift/Applescript writing. Trying to imagine the monorepos I've worked on running on a base Macbook Air... unless you're using it as an SSH frontend I don't think you'd be very productive.

I edited this comment to say colima. Colima is running a few containers that replicates our prod. We do use slim images, but why wouldn't we.

> Swift/Applescript writing

You dramatically underestimate the resources required to run Swift. I'm also developer license holder, and XCode brings the laptop to its knees. It is usable, but "XCode developers" are one of the small groups of people for who I'd recommend a ram upgrade.

Exactly, you know IT. I'm glad you can make it work. You aren't installing the crapware that comes with your logitech mouse, or running adobe suite, etc, etc. You know how to keep your computer clean and you only run what you need. You probably have a NAS set up for storage to avoid the fragile external drives and never fill your tiny 256GB storage accidentally.

Whereas all the not professional IT normal-people I see are having serious problems. Then again, I don't see them if they aren't having problems. Kind of selection bias. But when I need to fix these problems saying "We'll don't use that software." isn't acceptable. For PCs you just install more ram or upgrade to a new storage drive. For the modern macs? Buy a new one. It's pathetic.

So, theres a problem, but instead of addressing the root of the problem you just... install more RAM?

The reason I have 64GB of RAM in my daily driver Windows desktop is because all software are bloated and leaky pieces of shit to varying degrees, yes.

The solution presented is to not use your computer, kind of defeats the purpose though.

I'm sorry. I cannot fix the bloat in the software that people chose to use. I can't make Adobe Photoshop a real application anymore like it was up to CS2.

8gb ram is not fine because it's really a 10$, maybe less, production cost upgrade for 1000$ laptop. Even if it improves quality of life when using the laptop 10%, it still brings like 100$ of value to you.

The only reason Apple didn't put more RAM is to carve out the market for Pro models and squish money from consumers like you and me. There is no reason to defend corporation wishing to take more from a customer.

I agree. I just want to see people calling it out for what it is. 8gb of RAM is still perfectly usable. Saying it isn't is lying. Instead, say that Apple is gorging its customers, because that isn't a lie.

> Apple's irresponsible sales of unupgradable…

Every upgradeable component needs a socket to plug the thing into, along with the module needing the compatible plug design. This will add a non-zero amount of extra materials per laptop. Even just twice the amount of solder, never mind extra PCB space, copper and so on.

If you never upgrade within the lifetime of the device, then that is essentially waste. If the majority of people don’t upgrade then that could end up being significant.

You can also flip the irresponsibility back to software engineers. Are basic users really doing anything that needs 8Gb of RAM these days that you couldn’t do with much less 20 years ago? Why do we have RAM inflation?

Yep. Surprise! This is what happens when you replace 90% of your window views with WebKit processes rendering HTML. You'd think that Apple saw how poorly this ended for Windows, but no they just had to join in the fun too. No, zram is not a good enough excuse to suffer through 8gb of memory on a Mac.

Thank you Project Marzipan/Catalyst. I love having hundreds of Safari processes running my OS instead of native Cocoa, yessiree.

I thought Marzipan/Catalyst were still native, just bridged over from the mobile OSes. Are they really using web tech to render them?

OP is misrepresenting it, because its not just mac catalyst, its really everything. I don't understand the full scope, but there is definitely a browser renderer being used for text. See this[0], which I encountered only after days of confusion about why my text was looking suspiciously[1] like the default browser stylesheet

[0]: https://www.cocoanetics.com/2012/12/uitextview-caught-with-t...

[1]: https://shottr.cc/s/1O4j/SCR-20240811-2un.png

Catalyst apps are native, yes.

I don’t know what he’s talking about. Catalyst is actually pretty complex, and is indeed native — it seeks to bridge the API differences between uikit and appkit — it’s not the macOS equivalent of electron using webtech.

Got my mum an M1 a while ago and my dad an M3. Lowest spec. It’s been great. They used their old one for six years each. These laptops rule. Amortized cost of $200/year including opp. cost of laptop. Great value for money.

They can view x-rays and make presentations. Happy with that.

Well RAM can be an interesting trade off.

Have the last MacBook Pro Core i9 model with 64GB RAM and 4TB SSD and in trying to sell it the prices seem super low way less than 1k.

I bet the M2 is worth way more.

It’s already started compressing unused pages. In the old days we’d see those hit spinners.

Wow, it’s almost like the OS is taking up some ram and doing some OS related stuff. Which is perfectly normal and expected.

8gb RAM is completely insufficient these days.

Apple has been attempting to create a culture of scarcity for years, locking more ram away behind a thousand dollar upgrade when in reality it’s $20 worth of chips under a sane, user serviceable architecture.

Two of them is file cache, which still leaves with the base os consuming 2.71 GB ram out of 8, but it's never exactly eight... it's always a little less.

So basically an 8GB laptop is really a 6GB laptop. Yikes.

Also, it's already using ~540mb of swap memory... Swap usage will kill the flash chip pretty fast.

Besides everything, this will generate an incredible amount of e-waste.

It doesn't matter. People buy those toy computers for their style. It's a fashion statement, a status symbol. Style over substance.

Haha, do you remember when Apple said that "8GB Mac RAM is equivalent to 16GB RAM on other operating system", and just when the world started to laugh at them, mysteriously Altman got fired from OpenAI, and everyone forgot about Apple?

</half-ironic tinfoil hat off>

>gets the device targeted for people that do every task ever in a browser like students or corporate people >complains about ram

lol

My browser is using 32GB right now. 8GB is a joke.

And here my Chromebook with 8Gb ram has dozens of tabs and web apps open in Chrome, runs one VM with Android and another VM with Linux in turn running Firefox and more. All without breaking a sweat.

So, going to sound like an Apple apologist here, but a couple of times I tried to track memory usage on my Mac and it didn’t make sense. I looked up some articles about why processes seemed to be using massive amounts of RAM and others seemed to be reporting extremely small usages. The articles said basically that macOS RAM usage is hard to measure because Activity Monitor basically reports what the process thinks it has, not what is actually allocated. I can’t seem to find the article again so take this with a grain of salt I could just be yapping

The article is correct. It’s the amount of ram the program asked for (virtual memory I think) The kernel has reserved address space but has not used ram until the program accesses it.

There is a separate metric for ram actually in use by a program. But that number isn’t an ideal “ram used” because it doesn’t account for compression or swap.

Linux is basically the same.

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