Why is the SSD on my MBP so slow?

[Faize]

This shouldn't take "about 5 seconds" (which turned out to be closer to 30), it should happen faster than I can blink.

For reference, this is a 1 TB SSD on a 2023 M2 Pro MBP. Even a bargain basement QLC SATA SSD is faster than this.

 

[Honza1]

Run Disk Utilities First aid on it to check for any issues. When my SSD eventually failed, first obvious issues was it was much slower than expected. Good luck.

 

[chown33]

How full is the SSD?

Are only the reads slow, only the writes, or are they both slow?
A disk benchmarking app would show both numbers.
Otherwise there are Terminal cmds that can produce the numbers.

 

[bradbomb]

Also, what is the source of the copy? Is this a copy to and from different folders on the same SSD or is it on a different drive?

 

[Honza1]

Also, what is the source of the copy? Is this a copy to and from different folders on the same SSD or is it on a different drive?

Good point about the source, that could have major influence.
But if the copy would be from the same drive (just different folder), APFS Apple uses today will not copy anything, just make link to the same data and speed will be very high and independent of file size. APFS simply records that the same data are used in different file second time and is done.

 

[Nermal]

How many files are being copied? Typically a bunch of tiny files take a lot longer to copy than a few big ones.

 

[Basic75]

Also, what is the source of the copy? Is this a copy to and from different folders on the same SSD or is it on a different drive?

It looks like an application being installed, best guess: It's a copy from a disk image on the internal SSD to the internal SSD. @Faize ist that correct?

 

[Faize]

It looks like an application being installed, best guess: It's a copy from a disk image on the internal SSD to the internal SSD. @Faize ist that correct?

Yes, this is an application being installed from a dmg downloaded to the internal SSD.

 

[theorist9]

Yes, this is an application being installed from a dmg downloaded to the internal SSD.

In that case I'm wondering if there's more than just copying taking place here. I'd run some tests copying other files/folders of similar size to see if you get the same results.

 

[mr_roboto]

I don't think there's anything unusual going on here. Eclipse is a large and complex Java IDE, so it wouldn't be surprising if that application bundle contains thousands of files. SSDs are fast at doing things with lots of little files, but there's still a lot of random R/W overhead involved in copying so many directories and small files. You can't expect the same performance you'd see if copying a single 787MB file.

edit: For anyone not familiar with the concept, macOS applications are stored on disk as "bundles". A bundle is simply a folder whose name has a ".app" extension, and a standardized layout of resources in subdirectories inside that folder. By default, Finder hides the ".app" extension, and presents the bundle as if it's a single file, but you can right click an app and then click "Show Package Contents" in the contextual menu to explore the app bundle's internal file structure.

 

[dmccloud]

Eclipse seems to take forever to install on any device, which is another reason I ditched it on my machine. To be honest, there's several alternatives that are faster, more reliable, and have feature parity (if not more) than Eclipse.

 

[benwiggy]

1000 files of 1 Mb each take longer took copy than 1 single 1Gb file. There are overheads in starting and stopping each file. The Finder is also slower than, say, a copy from Terminal.