trash empties very slowly from SD card

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Level 1

28 points

trash empties very slowly from SD card

I recently discovered that emptying the trash containing files deleted from an SD card takes 4 to 5 seconds per file on my MacBook Pro. Much longer than writing the files to the disk required. I have the same problem with two SanDisk cards, one is 32 GB the other 256 GB both high speed. I am currently using the Sonoma OS on a MacBook Pro. I have used both with Nikon cameras, which was when I first discovered this. As an experiment , I reformatted the larger disc to Mac OS Extended and I have the same problem. It is only trash emptying. Reading and writing to both discs is fast.

MacBook Pro 16″, macOS 14.7

Posted on Mar 30, 2025 02:49 PM

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Answer 1

Yer_Man

Level 10

165,516 points

Mar 30, 2025 03:26 PM in response to Lee Miller2

First off, if you reformat the cards to Mac OS Extended then you won't be able to use them in your camera. That format has to be done in the camera - which is also the much faster way to erase a card: reformat it with the camera. The slownesss is pretty much inherent in the fact that the camera cards are FAT32.

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Answer 2

Mar 31, 2025 10:22 AM in response to Lee Miller2

Make sure NOT to use any 3rd party anti-virus apps that might cause problems like this (macOS built-in protection is all you need anyway). Also 3rd party "cleaners" should be avoided because they often corrupt the system.

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Answer 3

Mar 31, 2025 11:34 AM in response to Lee Miller2

Lee Miller2 wrote:

This is a university machine, for which they load on some additional security and administrative software. It strikes me that interfering with trash emptying, but not read/write/delete operations would be unlikely, but I suppose not out of the question.

Such organizations might be forced to use such unnecessary and harmful 3rd party anti-virus software on macOS.

One faster workaround might be to format the SD card if all its contents are deleted anyways. Or, better yet, just format the SD card in the camera which best knows what formatting options it supports.

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Answer 4

HWTech

Level 9

66,758 points

Apr 2, 2025 08:55 AM in response to Lee Miller2

If you are using a built-in SD Card Reader on the Mac, then try using an external USB SD Card Reader instead to see if that makes any difference. I have seen multiple posts on this forum where some SD Cards have problems with the M-series Macs' built-in SD Card Reader.

You may also want to check the speed of that SD Card using Black Magic Disk Speed Test available for Free in the Apple App Store. Flash media tends to slow down their write speeds when performing sustained writes. This may or may not show up in the Black Magic speed test depending how long the write portion of the test runs. You will need to make sure to select the volume on the SD Card as the destination for the benchmark test since it defaults to the boot volume.

Also, disconnect all other external devices just in case one of them is causing a problem or interference.

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Answer 5

Lee Miller2 Author

Level 1

28 points

Mar 30, 2025 04:10 PM in response to Yer_Man

Yes, I'm aware of the camera format issue, which is exFAT, not FAT 32. I've been using one of the cards (the smaller one) in a D7000 for well over decade, and it's always worked fine. Now it isn't slow, it's glacial. Emptying the trash for several hundred files takes 20-30 minutes. I reformatted the newer, bigger one (which I got for a new Z5) as an experiment to see if it was something intrinsic to the card(s). The formatting made no difference to the trash empty problem. It doesn't matter if it's image files from the camera or other files copied to the disk from the computer. Unless both cards suddenly decided to develop the same problem, I have to assume it's related to an OS update. Anyone else?

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Answer 6

Lee Miller2 Author

Level 1

28 points

Mar 31, 2025 07:01 AM in response to Lee Miller2

I have an update on the SD card trash-empty problem. I came up with an older MacBook running Catalina. The problem is not present there. Trash empties essentially instantaneously, as opposed to 4.5 minutes to empty 50 files from the trash on the MacBook Pro running Sonoma. Has anyone else seen behavior like this?

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Answer 7

Lee Miller2 Author

Level 1

28 points

Mar 31, 2025 10:59 AM in response to Matti Haveri

This is a university machine, for which they load on some additional security and administrative software. It strikes me that interfering with trash emptying, but not read/write/delete operations would be unlikely, but I suppose not out of the question.

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Answer 8

Mar 31, 2025 11:54 AM in response to Lee Miller2

What’s the speed rating on that “High Speed” SD card?

https://www.kingston.com/en/blog/personal-storage/memory-card-speed-classes

Irrespective of the “high speed” name, “high speed” is the second slowest SD available, and is the slowest meant for use in digital cameras:

https://en.wikipedia.org/wiki/SD_card#Speed

Emptying trash likely involves sending an erase (TRIM) command to the storage, and flash erasure is slow.

Erasing the whole thing will be faster.

Try a faster card?

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Answer 9

Lee Miller2 Author

Level 1

28 points

Mar 31, 2025 12:12 PM in response to MrHoffman

Thanks, but it's not the card speed, which is 200 Mb per second. Also, as I pointed out above, reading, writing, and deleting are as fast as expected. It's simply "emptying" the trash that is orders of magnitude slower than it should be. One more factoid, if I empty the trash through the terminal rather than the GUI, it is just as slow.

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Answer 10

Lee Miller2 Author

Level 1

28 points

Mar 31, 2025 11:41 AM in response to Matti Haveri

It never even dawned on me just to rely on camera formatting as a workaround. That's a great suggestion. It's still rather irritating that something weird is going on that I can't figure out.

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Answer 11

Mar 31, 2025 12:45 PM in response to Lee Miller2

200 Mbps is roughly UHS-2 and 20 MBps, well faster than the older speeds, so yeah, probably not the card.

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