exfat-fuse + Samba: unstability issue

[josephernest]

Hi @relan,
Congratulations for this great project and for making exfat filesystem available on Linux.

There might be an unstability issue when using exfat + Samba. Here is how to reproduce on a Raspberry Pi4.

1. Connect a USB3 external HDD to a RPi4, that you know being fast enough (temporarily create a ext4 partition on it and do dd if=/dev/zero of=/mnt/a/test bs=1M count=1000 to make sure it's at least 50MB/s)

2. Now create an exfat partition on the same disk, and create a read+write Samba share on it

3. From any other computer (use an ethernet cable and not WiFi since WiFi would be a bottleneck), Windows for example, go to the shared folder and copy a large file (e.g. 2 GB) to this Samba share. Direction: Windows => Rpi4 exfat partition

4. The Windows Explorer will start freezing / crashing. On the SSH RPi side, even ls is unresponsive. Once I got top working and very high CPU was used by FS related process.

Do you have any idea?

This doesn't happen with NTFS. See also https://raspberrypi.stackexchange.com/questions/118654/how-to-mount-a-veracrypt-container-on-a-rpi-with-optimal-performance/118693#118693

[heartbleeded]

I'm having the same issue with exfat-fuse & smb on ARM. You have any update on this ? @josephernest