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M1 Air SSD speeds
- Thread starter outlawarth
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That would be the first time I heard that, if true. I have the 256GB SSD in my M1 MBA and it's extremely fast, so I'd say save your money and stick with the 512GB unless you actually need the extra storage capacity.
I recollect reports over the years reporting that very reality — faster reads & writes with larger SSDs.
But I also recall that the major jump in speed happened between the base SSD, say 128GB or 256 GB, and the next tier up, e.g., 512 GB. The 512 GB to 1 TB speed increase wasn't nearly as dramatic.
Let's see what the tech mavens around here say about this — those who are immersed in such matters.
A little Internet searching via Duck, Duck, Duck Go will net you the old reviews of Macs and their SSDs and test results. That could be faster to get the info and you'd have it confirmed by multiple tech analysts.
But I also recall that the major jump in speed happened between the base SSD, say 128GB or 256 GB, and the next tier up, e.g., 512 GB. The 512 GB to 1 TB speed increase wasn't nearly as dramatic.
Let's see what the tech mavens around here say about this — those who are immersed in such matters.
A little Internet searching via Duck, Duck, Duck Go will net you the old reviews of Macs and their SSDs and test results. That could be faster to get the info and you'd have it confirmed by multiple tech analysts.
Generally, larger capacity SSD's have higher MTBF (mean time between failure) ratios. They fail less often than a smaller capacity SSD. I've never heard of a larger capacity SSD (same manufacturer/chipset) having faster read/writes, though that could vary by manufacturer. I'm here to learn something too, so those with the knowledge please chime in!
Anything that I have found doesn't show that the larger capacity SSDs are faster than smaller capacities (of course given they are the same technology), but according to Newegg that the capacity left in the SSD can affect speeds. So if you have a 256GB SSD but only 20GB is available, then the SSD is slower basically to find room to "find" the space to write more data.
https://www.newegg.com/insider/does...text=Are Larger SSDs Faster?,buy a 500 GB SSD.
https://www.newegg.com/insider/does...text=Are Larger SSDs Faster?,buy a 500 GB SSD.
Very interesting observations. Thank you for everyone’s input. I recalling reading somewhere about this but I can’t find it now.
I’m thinking of going with 512GB as I really don’t have a need for 1TB on this machine. I just wanted to make sure I’m not sacrificing performance between the two.
I’m thinking of going with 512GB as I really don’t have a need for 1TB on this machine. I just wanted to make sure I’m not sacrificing performance between the two.
So I have been curious about this since trying to look into it more and I stumbled across this old Macrumors post.
https://forums.macrumors.com/threads/does-ssd-size-affect-speed-in-the-pro-max-mbps.2321863/
It appears that the SSD size does affect speed in the MBP and from what I can gather this is because of the bus that are on the various size SSD, but at around 4TB it is pretty much capped with the biggest differences starting with the 1TB and as you go higher the differences don't seem that much greater. Going off the chart that is included in the post, it seems the 1TB has a decently greater write speed, but it would be up to you to determine if that much more money is worth it just for a little faster writing which technically slows down a little more the more you write to the SSD.
Edit: The charts were also with the M1 Pro and M1 Max MBPs too which could also slightly make a difference.
https://forums.macrumors.com/threads/does-ssd-size-affect-speed-in-the-pro-max-mbps.2321863/
It appears that the SSD size does affect speed in the MBP and from what I can gather this is because of the bus that are on the various size SSD, but at around 4TB it is pretty much capped with the biggest differences starting with the 1TB and as you go higher the differences don't seem that much greater. Going off the chart that is included in the post, it seems the 1TB has a decently greater write speed, but it would be up to you to determine if that much more money is worth it just for a little faster writing which technically slows down a little more the more you write to the SSD.
Edit: The charts were also with the M1 Pro and M1 Max MBPs too which could also slightly make a difference.
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Interesting find. As you said the biggest gains are up to 1TB and after that it becomes moot.
I actually purchased both a 512 GB MacBook Air and a 1 TB MacBook Air this weekend. (I returned the 512 GB model.)
Blackmagic results:
512 GB
2480.3 MB/s WRITE
2930.2 MB/s READ
1 TB
3039.6 MB/s WRITE
3012.3 MB/s READ
I ran it a few times, and the numbers were a bit all over. The WRITE speed for the 512 GB laptop always seemed to be the lowest number.
Blackmagic results:
512 GB
2480.3 MB/s WRITE
2930.2 MB/s READ
1 TB
3039.6 MB/s WRITE
3012.3 MB/s READ
I ran it a few times, and the numbers were a bit all over. The WRITE speed for the 512 GB laptop always seemed to be the lowest number.
My SSD in my 1 TB M1 MacBook Air seems to have slowed down slightly over time. With BlackMagic Disk Speed Test with a 5GB test I'm seeing 2700 write and 2800 read. It was definitely in the low 3000's when I first got it on the M1 MBA release day at the end of November 2020. I have about 375 GB free but that doesn't include a 100 GB in snapshots (or at least whatever purgeable is). I suspect the SSD is slower because in reality, the drive is almost 80% full with the snapshots.
