Performance difference in SSD size?

[AltecX]

I know some machines there is a difference in the speed of a 256GB SSD and a 1TB SSD. Is this the case in the M1 machine as well?

 

[Fishrrman]

There may be some speed differences.
Larger SSDs -- at least in the past -- tended to be a little "faster" than smaller ones.

But I sense that ALL of Apple's new SSDs are "fast enough" so that the user will almost never "notice a difference" between them in real world usage...

 

[darngooddesign]

I remember someone posting benchmarks showing that the 256 drive was around 20% slower than the 512 and larger drives.

 

[malcky77]

I always thought it mattered more based on space available on the SSD…as in a nearly full large capacity SSD would benchmark slower than a lightly filled small capacity SSD?

 

[darngooddesign]

I always thought it mattered more based on space available on the SSD…as in a nearly full large capacity SSD would benchmark slower than a lightly filled small capacity SSD?

That's assuming both drives have the same read/write speeds.

 

[CWallace]

I know some machines there is a difference in the speed of a 256GB SSD and a 1TB SSD. Is this the case in the M1 machine as well?

As I understand it, the more nodes an SSD has, the faster it performs due to being able to read/write in parallel. So larger SSDs have more nodes and therefore perform faster.

In posts of testing Apple SSDs, I recall the jump from 256GB to 512GB was the biggest, with 1TB, 2TB, 4TB and 8TB capacities adding only a bit more performance over the capacity below it.

 

[jerryk]

I remember someone posting benchmarks showing that the 256 drive was around 20% slower than the 512 and larger drives.

That may be the case, but does it matter in real life given human time perception given the high speed of these drives?

M1 drives transfer up to 2100 MB/sec (2.1 GB/sec). So unless you are transferring some massive files a lot or just need the space, it is hard to see spending hundreds of dollars to transfer at 2.1 GB/sec versus 1.7 GB/sec.

 

[darngooddesign]

That may be the case, but does it matter in real life given human time perception given the high speed of these drives?

M1 drives transfer up to 2100 MB/sec (2.1 GB/sec). Unless you are transferring some massive files a lot it is hard to see spending hundreds of dollars to transfer at 2.1 GB/sec versus 1.7 GB/sec.

Probably matters more on the 8gb Macs where the SSD is being used for application scratch, OS swap, and reading/writing files.

 

[jerryk]

Probably matters more on the 8gb Macs where the SSD is being used for application scratch, OS swap, and reading/writing files.

If some is faulting at a high enough rate to push the memory pressure graph into yellow or red then they need to look at expanding their memory first. Writing pages to memory and then having to nearly immediately swap them back in to run is something you want to avoid no matter how fast the drive is.

 

[DaveFromCampbelltown]

The internal SSD on my iMac is 4 times faster than my external SAMSUNG T3 & T5 SSDs. However, I don't notice any difference between normal operating speeds. Once you get past 400 MB/Sec, the OS overhead swamps the speed of the SSD.

 

[AndyMacAndMic]

I know some machines there is a difference in the speed of a 256GB SSD and a 1TB SSD. Is this the case in the M1 machine as well?

The SSD in the M1 is a very good and fast one, but still has the same technical limitations as any other SSD.

So, the following explanation applies to the M1 too:

https://www.howtogeek.com/248827/why-are-smaller-ssds-slower/

If you will notice it in real life depends on your personal use case and is another question alltogether.