Extremely slow file transfer speeds on OS Ventura

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.

I was able to "solve" it by disabling Spotlight search on the specific external drive. Settings > Siri and Spotlight > Privacy > Add the external drive to the list to disable Spotlight indexing.

Takes a few minutes to kick in and then copy speed goes back to pre-Ventura days.

For whatever it's worth, I'd suddenly been having this issue as well transferring files and backing up photos to various hard drive types on my M1 14" running 13.4.1 with plenty of memory and disk space and It occurred to me that it all began after I updated Clean My Mac X. While I do make use of the app regularly to get rid of unnecessary files and other things taking up space and potentially slowing things down, I figured if that was the culprit, I could live without it. I figured it was likely due to, like Spotlight, it constantly indexing and that creating some sort of conflict with file transfers.

Lo and behold, I trashed it and immediately, without even having to reboot anything, the 618 GB of files I was moving went from 6 days to 2 hours.

I may try to reinstall it at some point and see if it plays nice, but if it does the same thing, I'll definitely prefer to live without it.

I found the issue I was having, not software related, aparently.

tldr; it's the USB cable, use the original cable, or perhaps some advanced aftermarket mystery cable.

Because I was using a cable from my other SSD enclosure "Orico USB-C Adapter 10Gbps USB3.2 Gen2", and experienced the issue. Yet my other SSD drive works at 1000MB/s with the same cable.

The cable seemingly worked, at least on other machines with Samsung T7, not anymore aparently, write speeds were turtle level 20 minutes 4GB. Now I use original USB-C>USB-A cable(incl. with the drive), with a 10Gbps USB-C HUB, and the speed is back to 700MB/s... I don't have USBC both ends, with me.

More history: I actually had the previous Samsung T7 drive sent to warranty, a 6month nightmare, until I got a new one. For the old one, none of the cables, including the original didn't work in speeds beyond 40MB/s, on any system. I believe the drive stopped working normally when I inserted it into a laptop, which had problems with USB-C port, but I'm not too sure, because I sold the laptop, and refused to try the replaced drive with it.

I wanted to copy 24GB to my USB. 58 days were set as the time needed. It was just sitting there, a kb or so.

So I went to the utility disk. Erases the disk and set to Mac OS extended (journaled)

Didn't change much as it was already formatted as Mac OS.

Went to settings - Sir and spotlight. At the bottom Privacy. Then hit the + and then wait for the USB to turn up and choose.

Eject the USB, Insert the USB. Start the copy.

Now at 23 mins for 24GB. That's OK.

Hi

May have a solution

I had the same slow transfer speeds for memory sticks since installing Ventura 13.0.1. My memory sticks were formatted to exFat (for moving files between a Mac and PC), I have just used the disk utility on my MBPPro (2017) and erased and reformatted the memory sticks to Mac OS Extended (Journal) and the transfer speeds are back up to normal.

NB Memory Sticks nothing special a couple of SanDisks 64GB and 128GB, one was a USB 2 with a USB C adapter the other was a dual USB C/USB 2 connection memory stick.

Hope this helps

I uawd the Thunderbolt 3 (USB-C) Cable instead of using the USB-C to USB2.0. I was able to copy 200GB in an hour to a SAN Disk.

All I can do is copy and paste what I just said in the other thread...

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.

VPNs, A/V, cleaning and other similar apps have been shown to interfere with the system's operations. Unless you're using a true VPN tunnel, such as between you and your employer, school or bank's servers, they are useless from a privacy standpoint.  Read these two articles: Public VPN's are anything but private and Former Malware Distributor Kape Technologies Now Owns ExpressVPN, CyberGhost, Private Internet Access, Zenmate, and a Collection of VPN “Review” Websites. 

They just reduce your bank account and interfere with normal system and application performance.

That's too bad. 13.3.1 did fix this issue for me on two computers, a Macbook Pro M1 and a Mac Studio Ultra.

Disabling spotlight for my Drobo (on a Macbook Pro 16") worked for me, too.

Thanks so much.