slow flash drive write speed

[brudan]

I have a USB3-capable flash drive that holds a single 16GB fat32 partition. I need fat32 because this flash drive is used on OpenBSD, GNU/Linux, and also Windows (imposed at work). In the tests below I'm plugging this flash drive into the same USB2 port of my T400 ThinkPad.

When booted into my GNU/Linux partition, I can copy a 260 MB test file to this drive in 18 seconds.

When booted into my OpenBSD 6.4 partition, it takes 120 seconds to copy the same file to the drive.

I tried mounting the drive in OpenBSD with all of these commands, with similar results:

# mount /dev/sd1i /home/bruno/usb
# mount -o async /dev/sd1i /home/bruno/usb
# mount_msdos -u bruno -g bruno /dev/sd1i /home/bruno/usb

Surely OpenBSD must be capable of writing to a flash drive faster than 2.1 MB/sec, so the problem must be me. What am I doing wrong? I've been going around in circles and am not sure what else to try.

P.S. I also tried formatting the drive to ext3 (even though I can't keep it as ext3 for because of forced Windows at work) and got similar write speeds.

[Prevet]

120 seconds? Is that all? When I first came to OpenBSD I tried copying files to USB sticks. The first 40MB would be fine, but after that it slowed to a crawl, and would take hours to copy 1GB. Very frustrating. After that I just used the network to copy files between different file systems.

OpenBSD doesn't have the resources of Linux, where big megacorps have their fingers in it. A small number of people work on it, it is security focused, and is designed to be a server. So if you transfer files the way it was designed to, you won't have any problems. If your issue Isn't resolved in this thread then copy the files to a second Win or Linux machine, and copy them to OpenBSD over the network. But 120 seconds isn't worth it.

[fvgit]

Your speeds seem pretty normal (for OpenBSD), I dare say.

 time cp test.img /mnt/                                           
    2m11.16s real     0m00.00s user     0m01.84s system

That's a 260M image file of random data copied to a FAT32 formatted (newfs_msdos(8)) USB stick attached to a USB 2.0 capable controller on my ten year old laptop. Took 131.16 seconds to copy. You'll just have to live with it.

[brudan]

Thank you very much, Prevet and fvgit. I assumed there was a problem with either my system or with my understanding, so you just saved me hours of troubleshooting and chasing my tail on this.

If this is part of the price to pay in order to use a secure and elegant system that is put together by scrupulous developers who are in no way beholden to megacorps, count me in!

Thanks again for confirming that this is normal for OpenBSD.

[hermano]

Ayup - I can also confirm that OpenBSD writing to a USB widget is about 5 times slower than other systems. Why this is, I haven't the foggiest.

[sacerdos_daemonis]

Originally Posted by hermano

I can also confirm that OpenBSD writing to a USB widget is about 5 times slower than other systems.

On some devices yes, but on others no. I have a new 16GB flashdrive and two 500GB external hard-drives that are both several years old. OpenBSD writes to them significantly quicker than the Windows system in the office downstairs. Windows on computers in the teaching building write to those devices at about the same speed as my OpenBSD. A flashdrive I threw away worked normally on Windows but OpenBSD took forever to write to it. Five to ten minutes to write 100MB! I do not know if my experience typical, but I have found that different devices react differently to the system.