6 ms·

Remember it's not 8gb of dedicated RAM. It's 8gb shared with the video subsystem. Let's see how far that goes when you plug it into a 4K monitor and/or do anyth

by jmyeet 4y ago

Remember it's not 8gb of dedicated RAM. It's 8gb shared with the video subsystem. Let's see how far that goes when you plug it into a 4K monitor and/or do anything that requires GPU acceleration (which can include simply decoding video). I think 8gb is borderline criminally low in the circumstances. At least this thing has the option for 24gb though. I just wish that was a stocked model so you could just walk into a store and buy one without having to order it.

eropple 4y ago
For what it's worth--when I had an 8GB Air, decoding video in a browser didn't seem to really impact performance. Plugging in an external monitor, though, was not a fun time.
- rolleiflex 4y ago
  I have a 32Gb M1 Pro as a work laptop and connecting a retina 4K external display is not a fun experience for me either. It was very surprising to see it fail to maintain 60fps in the OS’ own animations.
  - phren0logy 4y ago
    That seems like something is wrong - if this is a known issue with such capable hardware I'd find that shocking
  - whynaut 4y ago
    Are you using the built-in HDMI port, or a dongle? I had the same issue before switching off the dongle.
    - rolleiflex 4y ago
      This is through USBC which also charges the laptop.
      - eropple 4y ago
        Is the connection handling HDMI natively, or via DisplayLink? I could definitely see performance issues being accentuated for DisplayLink.
bdhess 4y ago
I use my 8 GB M1 Air with a 5K display regularly and the only situation where it struggles is gaming. Browsing with zillions of tabs, video, etc is beautiful and lag free.
1123581321 4y ago
The SoC contains hardware decoders and external monitors don't require a lot of video memory per se.
- smoldesu 4y ago
  > and external monitors don't require a lot of video memory per se. That depends. Your average 1080p display doesn't really use a ton of video memory, but a 5k display connected to an internal 1440p display? That's a pretty huge framebuffer. AFAIK, Quartz also has a separate video buffer for each individual window, ranging from 50-150mb for the average application. Add it all up, and I agree that 8gb is pretty low, even with swap. Macs are memory-hungry devices, limiting your physical memory to 8gb is going to be really difficult to work with on anything that isn't text editing or light web browsing.
  - 1123581321 4y ago
    I agree you hit memory limits per application if you run a lot at once, but WindowServer roughly uses about 10-20% more memory on 4-5k vs. 2k, running the same applications. The 1080 plus the external, perhaps 15-25%. I'm not saying this means 8GB is the right amount of RAM for you.
  - adrr 4y ago
    How many people are using external display on an entry level laptop? Think of all you family members and friends who aren’t in the software field. I don’t even use an external monitor on my personal laptop and its MBP 16” Pro with 32GB of ram. At most I side car an Ipad but that is more power user stuff. Air with 8 GM of ram is perfect for a personal laptop where your primary focus is web browsing, watching media and occasional video/photo editing.
    - smoldesu 4y ago
      > Air with 8 GM of ram is perfect for a personal laptop where your primary focus is web browsing, watching media and occasional video/photo editing. I hear people say that today, but how is it going to feel in 2025, when you try loading up MacOS 16 on it? Given the trend of Apple's development, I don't think 8 gigs is going to be sufficient for most people going forward. That's basically iPad-tier memory constraints on a desktop-class operating system.
numpad0 4y ago
This just occurred to me: They should add DRAM interface to M chips. Or maybe a RAM over PCIe device. Those RAM chips are gigantic off-die cache, can't replace RAM.
lalaithion 4y ago
I have an 8gb M1 Air, and use it plugged into a 1440p monitor while watching video or in video calls. Maybe 4k would make a difference, I don't know—but most people don't have 4k monitors. 8gb is perfectly fine for me, and I'm probably in the top 10% of users as far as being a power user goes.
lowbloodsugar 4y ago
>I think 8gb is borderline criminally low in the circumstances. I think Apple has a far better understanding, backed by actual data, of the circumstances than you, or indeed anyone here. My wife is still using her 2015 Air and has yet to plug it into anything, let alone 4k or 5k monitors that appears to be the "end game scenario" for posters here. If you are posting on HN, then 8GB is not enough for you. I bought a 16GB M1 Air and it was great, and the day it came out I bought a 64GB M1 Max. But 8GB is more than enough for most of Apple's customers, and I'm sure they have the data to back that up.
- jmyeet 4y ago
  I think you’re overstating the technical weight going into this decision. I think it’s almost all marketing. Remember the 16gb iPhone? It really just existed to make the 32/64gb models look more reasonable and so Apple could say “From $lower_price_point”.
  - lowbloodsugar 4y ago
    Confused by your reply. It is absolutely all marketing. Driven by data. They know their market, and the market for an 8GB M2 Air is not the HN crowd. Further, they know that the HN market exists, and will pay more for 16GB.
- mixmastamyk 4y ago
  If you mean data from the Finance department, yes. In the cheapest M2/disk combo, threads here have said Apple have crippled the storage bandwidth relative to the M1, so relying on fast virtual memory is no longer an option. In that scenario 8GB is even more constraining than it was a year ago. https://news.ycombinator.com/item?id=31962854 https://news.ycombinator.com/item?id=31962854
jmull 4y ago
For a frame of reference, one full frame buffer for a 4K monitor is around 32MB. Put another way, you can have about 32 of them per GB of RAM. Not that you can’t use plenty of GPU RAM, but 8GB gives you a lot of room to work with. (Video decoding need all that much — probably three buffers worth per stream, and at the size of the video, not the screen.)
- ohgodplsno 4y ago
  If you think a compositor only holds a single frame buffer (or even up to three), boy do I have some news for you about the last 30 years.
  - jmull 4y ago
    I think you're misunderstanding my comment.
bluedino 4y ago
> Remember it's not 8gb of dedicated RAM. It's 8gb shared with the video subsystem. Just as it was before, with the Intel chips. Sure you had 64MB of eDRAM or whatever they called it as a cache but you were still using system memory for video.

by jmyeet 4y ago

eropple 4y ago

For what it's worth--when I had an 8GB Air, decoding video in a browser didn't seem to really impact performance. Plugging in an external monitor, though, was not a fun time.

rolleiflex 4y ago
I have a 32Gb M1 Pro as a work laptop and connecting a retina 4K external display is not a fun experience for me either. It was very surprising to see it fail to maintain 60fps in the OS’ own animations.
- phren0logy 4y ago
  That seems like something is wrong - if this is a known issue with such capable hardware I'd find that shocking
- whynaut 4y ago
  Are you using the built-in HDMI port, or a dongle? I had the same issue before switching off the dongle.
  - rolleiflex 4y ago
    This is through USBC which also charges the laptop.
    - eropple 4y ago
      Is the connection handling HDMI natively, or via DisplayLink? I could definitely see performance issues being accentuated for DisplayLink.

bdhess 4y ago

I use my 8 GB M1 Air with a 5K display regularly and the only situation where it struggles is gaming. Browsing with zillions of tabs, video, etc is beautiful and lag free.

1123581321 4y ago

The SoC contains hardware decoders and external monitors don't require a lot of video memory per se.

smoldesu 4y ago
> and external monitors don't require a lot of video memory per se. That depends. Your average 1080p display doesn't really use a ton of video memory, but a 5k display connected to an internal 1440p display? That's a pretty huge framebuffer. AFAIK, Quartz also has a separate video buffer for each individual window, ranging from 50-150mb for the average application. Add it all up, and I agree that 8gb is pretty low, even with swap. Macs are memory-hungry devices, limiting your physical memory to 8gb is going to be really difficult to work with on anything that isn't text editing or light web browsing.
- 1123581321 4y ago
  I agree you hit memory limits per application if you run a lot at once, but WindowServer roughly uses about 10-20% more memory on 4-5k vs. 2k, running the same applications. The 1080 plus the external, perhaps 15-25%. I'm not saying this means 8GB is the right amount of RAM for you.
- adrr 4y ago
  How many people are using external display on an entry level laptop? Think of all you family members and friends who aren’t in the software field. I don’t even use an external monitor on my personal laptop and its MBP 16” Pro with 32GB of ram. At most I side car an Ipad but that is more power user stuff. Air with 8 GM of ram is perfect for a personal laptop where your primary focus is web browsing, watching media and occasional video/photo editing.
  - smoldesu 4y ago
    > Air with 8 GM of ram is perfect for a personal laptop where your primary focus is web browsing, watching media and occasional video/photo editing. I hear people say that today, but how is it going to feel in 2025, when you try loading up MacOS 16 on it? Given the trend of Apple's development, I don't think 8 gigs is going to be sufficient for most people going forward. That's basically iPad-tier memory constraints on a desktop-class operating system.

numpad0 4y ago

This just occurred to me: They should add DRAM interface to M chips. Or maybe a RAM over PCIe device. Those RAM chips are gigantic off-die cache, can't replace RAM.

lalaithion 4y ago

I have an 8gb M1 Air, and use it plugged into a 1440p monitor while watching video or in video calls. Maybe 4k would make a difference, I don't know—but most people don't have 4k monitors. 8gb is perfectly fine for me, and I'm probably in the top 10% of users as far as being a power user goes.

lowbloodsugar 4y ago

>I think 8gb is borderline criminally low in the circumstances. I think Apple has a far better understanding, backed by actual data, of the circumstances than you, or indeed anyone here. My wife is still using her 2015 Air and has yet to plug it into anything, let alone 4k or 5k monitors that appears to be the "end game scenario" for posters here. If you are posting on HN, then 8GB is not enough for you. I bought a 16GB M1 Air and it was great, and the day it came out I bought a 64GB M1 Max. But 8GB is more than enough for most of Apple's customers, and I'm sure they have the data to back that up.

jmyeet 4y ago
I think you’re overstating the technical weight going into this decision. I think it’s almost all marketing. Remember the 16gb iPhone? It really just existed to make the 32/64gb models look more reasonable and so Apple could say “From $lower_price_point”.
- lowbloodsugar 4y ago
  Confused by your reply. It is absolutely all marketing. Driven by data. They know their market, and the market for an 8GB M2 Air is not the HN crowd. Further, they know that the HN market exists, and will pay more for 16GB.
mixmastamyk 4y ago
If you mean data from the Finance department, yes. In the cheapest M2/disk combo, threads here have said Apple have crippled the storage bandwidth relative to the M1, so relying on fast virtual memory is no longer an option. In that scenario 8GB is even more constraining than it was a year ago. https://news.ycombinator.com/item?id=31962854 https://news.ycombinator.com/item?id=31962854

jmull 4y ago

For a frame of reference, one full frame buffer for a 4K monitor is around 32MB. Put another way, you can have about 32 of them per GB of RAM. Not that you can’t use plenty of GPU RAM, but 8GB gives you a lot of room to work with. (Video decoding need all that much — probably three buffers worth per stream, and at the size of the video, not the screen.)

ohgodplsno 4y ago
If you think a compositor only holds a single frame buffer (or even up to three), boy do I have some news for you about the last 30 years.
- jmull 4y ago
  I think you're misunderstanding my comment.

bluedino 4y ago

> Remember it's not 8gb of dedicated RAM. It's 8gb shared with the video subsystem. Just as it was before, with the Intel chips. Sure you had 64MB of eDRAM or whatever they called it as a cache but you were still using system memory for video.