Extremely slow external SSD read and write speed after Ventura update - MacBook Pro 16 M1 Max

Hurray I've solved the problem,I experienced my drives get slow

immediately I upgraded from Monterey to Ventura so I was sure all my

drives were fine since 30 mins before they were working fine on Monteray before the upgrade.

Here's what I did I figured that since my external

hard drive activity light was continuously blinking probably a process

that was utilizing the drive, my guess was Spotlight search was indexing

my drive so I added it to the privacy exclusion list by going to system

settings, then Siri & spotlight and at the bottom selecting

spotlight privacy, I then dragged and dropped my external drive to the

exclusion list then selected done, now every drive I add to the

exclusion list works fine, ANOTHER OPTION would be to leave your drives pluged in and let spotlight finish indexing them and they will work just fine after some time though it may take a while to index them so be patient.

I had this issue with macOS 13.1 as well, however the macOS 13.2 update has fixed it for me today.

Benchmarks with Blackmagic Speedtest and a External Thunderbolt 3 enclosure with a Samsung 980 Pro 1TB:

macOS 12.x

Write - Read

2106MB/s - 2755MB/s

macOS 13.1

1186MB/s - 1675MB/s

macOS 13.2

2063MB/s - 2752MB/s

Improvements with my Samsung T7 SSD too.

Similar issue on 2021 16" MBP M1 Pro 16GB after updating to Venture. Issue is also with SD cards. Seems the faster the SSD or SD card, the worse it is bottlenecked.

USB-C SSDs:

• SanDisk Extreme SSD (Gen 1): 244 MBps write, 308 MBps read
  • 550 MBps rated (this drive used to get about 480 MBps up write and read on Monterey)
• Samsung T5: 150 MBps write, 480 MBps read
  • 540 MBps rated (this drive used to get about 480 MBps up write and read on Monterey)
• Samsung T7: 200MBps write, 600 MBps read
  • 1,000 MBps rated (this drive used to get about 720 MBps write and read on Monterey)
• Kingston XS2000: 95 MBps write, 650 MBps read
  • 2,000 MBps rated (this drive used to get 720 MBps write and read on Monterey)

*All drives tested on Ventura 13.0.1 using BlackMagic Disk Speed Test

*All drives tested on Windows 11 using CristalDiskMark8 and have no speed issues using the same cable

SD Card (using built-in reader):

• Kingston UHS-II U3 V90: 33 MBps write, 193 MBps read
  • 300 MBps rated
• SanDisk Extreme UHS-I U3 V30: 53 MBps write, 78 MBps read
  • 150 MBps rated
• SanDisk Extreme Pro UHS-I U3 V30: 48 MBps write, 81 MBps read
  • 170 MBps rated

*All drives tested on Ventura 13.0.1 using BlackMagic Disk Speed Test

Troubleshooting:

• Wiped and did a fresh install of MacOS Ventura 13.0.1 with no restore from backup
• Checked SSD life and firmware using Samsung Magician and Kingston SSD Manager
• Reformatted all drives using FAT, exFAT in both MBR and GPT schemes
• Tried multiple known good USB-C cables

The 2021 MBP M1 Pro 16" already had issues with USB-C drives due to not including USB 3.2 Gen 2. This just adds insult to injury for video editors.

I had similar issues after I installed a new copy of Ventura (holding down powerputton and choosing to install a fresh verison but keep all data)

My slow Samsung T7 (read 35MB) was tested with 3 differend usb-c cables, but with the 4th it had the normal read speed of 740 MB/s (very happy to find out. Also with the 5th cable, it worked great. It you look at the usb-c connector, all pins should be there, otherwise it will be a slow cable.

My quick Prograde v60 SD cards were also slow after the Ventura reinstall. 70 write / 80 read. After I deleted Black Magic Disk Speed app and feinstalled it, the same SD was good again with 160 write and 235 read.

hope this helps

I just needed to wipe my main computer to rollback from Sonoma recently and I confirm: installing Ventura directly on my MacBook Pro 16" Intel 2019 reproduced the issue (which I hadn't had before when I was on Ventura not too long ago).

Here's the full picture:

• External SSD of 1TB was plugged with a sata adapter through any of my 4 USB-C ports
• The disk is formatted as APFS and was a full system backup of my Sonoma install
• The disk was constantly reading (noticable noise) even though there was nothing happening
• The disk was added to spotlight exclusion right away to make sure it wouldn't interfere
• Reads were extremely slow - loading the list of files was excruciatingly slow and it seemed to have more trouble with files that had specific icons (not folders, but pdfs, apps, images, etc.)
• Copying files from the SSD to my computer was extremely slow (5mb/s, sometimes slower), regardless of the method used
• Copying methods tried: copying from Finder, cp command from terminal, rsync command from terminal, ditto command from terminal, some GUI rsync apps were tried
• The disk was running extremely hot over a short amount of time.
• I tried to plug it in with a different sata adapter (direct sata to USB adapter and Wavlink dual disk hub) and it didn't change anything, neither on speed nor on running hot

In the end, I scrolled past so many answers to this problem on every single link I could find from Google and one person suggested what ended up working for me - might be in this thread, but I can't find it anymore, credits to where it's due.

The solution was to not install Ventura, but Monterey and THEN upgrade to Ventura. What I ended up doing is restoring most of my files on Monterey to make sure I wouldn't run into the issue again, but I'm doing tests now that I have upgraded to Ventura again and the disk is of a normal temperature, mounts faster, reads faster, and copies faster. I'm averaging copy speeds of 250mb/s.

TL;DR: Install Monterey and then update to Ventura. DO NOT INSTALL VENTURA RIGHT AWAY. If you buy a computer that comes with the latest Ventura installed, test it out and if you have this issue, before doing anything serious with your computer, you might want to create a bootable USB drive and install Monterey THEN update to Ventura.

i have the same problem

when i plug my WD elements or every other HDD - it just so slow - thumbnails of my .raw files loads extremely slow it doesnt even load on every .raw file...

today i tried to plug the same HDD into my friends mcb air M2 which has Monterey and it loaded instantly every .raw file with thumbnails

im am running on mcb 2021 14" base model (512ssd, 16gb ram, M1 Pro)

i tried to make a different user, run my mcb in safe mode, tried to turn off every login item, tried to uninstall everything and delete remaining files, tried to run apples diagnostics and i even brought my mcb into authorized service in my country (ITS) and everything is okay with my laptop.

i had a conversation with another person with the same issue and he:

downgraded from ventura to monterey and the issue with slow hdds, ssds, sd cards are gone. he even tried to reinstall fresh ventura but that didnt helped either.

did anyone solved this issue? thank you

this is a new information that i got from my friend:

so an update after wiping my mac and going back to Monterey, I was feeling brave and updated to Ventura again (I don’t know why but yeah) and can confirm the issue is no longer present.

So I’m now running Ventura with full speed SSD, it just took a while to get here.

So to recap- Backup, full wipe from recovery, reinstall OS via recovery, setup in Monterey, update to Ventura and test.

Long as F**k process but it works as intended now.

I have a iMac (Retina 5K, 27" 2017 with 24MB ram) running on an external 1TB thunderbolt drive and get 23000MBs read and write under Mojave booting up took about 50Secs decided to install Ventura by doing a clean install erasing the drive first and boot time went to 3 minutes before installing apps took 1 minute to fire up outlook and the response was so bad it was a non starter..

Note: using thunderbolt external drive as my iMac has a 1TB fusion drive which is really slow and its way cheaper than sending iMac for upgrade to internal SSD

Tried Monterey same result, then tried Big Sur and boot time went to 50 secs and starting outlook for first time took about 10 secs.

On Researching it looks like Apple broke something with the external busses thunderbolt and usb but I don't see anything from them to say that it has been confirmed and working on a fix so my recommendation is don't go any higher than Big Sur if you have any external drives that you need for performance

Had the same problem so changed out the USB-C cable for a Thunderbolt cable and now Sandisk Extreme is back up to speed.

RomanHuber wrote:

Do people working at Apple ever take a look at their own forum/Community section?

No. This is a user-to-user support forum. If we can't reproduce the error, all we can do is direct you to one of:

Product Feedback - Apple - for general feedback, or

https://feedbackassistant.apple.com/ - to write a bug report. You may have to create a free developer account.

This kind of problem can be difficult. The general flow is always the same:

1) There is a change since installing (insert this year's operating system version here).

2) Ergo, there must be a bug in (version).

3) Me too!

4) Me too!, etc.

But at this point, it's a dead end. There is obviously no fundamental change in Ventura. Only a handful of people are reporting this problem. Possible causes are as follows:

1) Software conflict from some low-level system modification software

2) Hardware conflict from some other attached device

3) Hardware failure either internally or with the external device

I understand that this is not what anyone wants to hear. But I've seen this pattern repeated so many times, over so many years.

In most cases, people have no idea what low-level system modifications are installed and running. They also often only have vague ideas about what external hardware is connected. If you have specifics, you can post them. Maybe there is some common thread that would explain it.

You can try things like booting in safe mode. Or you can erase the hard drive and reinstall the operating system. Then run your test again before reinstalling any 3rd party software. If you still have the problem, then it is definitely a hardware problem. You can can take the computer and the external to an Apple Store and maybe get it fixed (assuming the failure isn't in the external).

If you don't want to do any drastic debugging efforts like that, then your options are severely limited. You can submit bug reports. If 10 thousand people have similar problems and they submit bug reports too, then Apple engineers might look through your reports and see if they can identify any common threads. But don't get your hopes up on this. It virtually never happens. And if it does, it takes months or years.

I'm not trying to start any fights here. I'm just trying to set expectations.

I have a iMac (Retina 5K, 27" 2017 with 24MB ram) running on an external 1TB thunderbolt drive and get 2300MBs read and write under Mojave booting up took about 50Secs decided to install Ventura by doing a clean install erasing the drive first and boot time went to 3 minutes before installing apps took 1 minute to fire up outlook and the response was so bad it was a non starter..

Note: using thunderbolt external drive as my iMac has a 1TB fusion drive which is really slow and its way cheaper than sending iMac for upgrade to internal SSD

Tried Monterey same result, then tried Big Sur and boot time went to 50 secs and starting outlook for first time took about 10 secs.

On Researching it looks like Apple broke something with the external busses thunderbolt and usb but I don't see anything from them to say that it has been confirmed and working on a fix so my recommendation is don't go any higher than Big Sur if you have any external drives that you need for performance

Hi LVLeleven,

I am experiencing the same issues. I do video edits straight from my SanDisk SSD. Yesterday I "upgraded" to Ventura and since then I couldn't work/edit off of my SSD properly as it was super laggy/slow. I just transferred the Final Cut file to my internal SSD on the Mac. Now it works super smooth again. I hope someone at Apple reads this and provides a solution to this option.

I have no idea if going back to Monterey works/is possible :-/ I wish I hadn't done the update.

Kind regards,

Roman

This isn't a format issue. Format issues would cause a slowdown if the partition map was badly corrupted and the OS didn't detect it while mounting. That would be more along the lines of a read or write failure than a slowdown. I only mentioned this to note that the drives and cards had been freshly formatted.

APFS can speed up the process of the OS checking for free space before a write, and things like things like that, but this is more an issue with the USB bus driver/controller in MacOS.

Looks like it dates back to the Ventura betas.