Rpi 4 Usb Disk Writing Speed

Hello everyone,

I’m using Dietpi with “Proftp + emby + deluge + pihole” which is installed to Rpi 4 2gb version.

I have some writing speed problems when I’m using HDD. I’m transfering files from computer to dietpi with using Proftp (dietpi) and filezilla (windows). While uploading files sending speed not stable it changes between 0 to 11mb/s. Transfer starts fast enough like 20mb/s and after passing 2 seconds it gets slow down to 5mb/s. Then stops some time for a second or 10sec. Than continuos stable 5mb/s. You can find the details of my disks end of this topic. I added htop details over ssh to end.

I’m using gigabit switch which is computer, router, dietpi, TV is connected. My router has 100mbit ethernet ports. My computer and dietpi is using Gigabit ethenet while connecting to eachother (Because of the gigabit switch which i said).

I don’t understand whats happening and why disk is so slow.

Proftp and dietpi-drivermanager test results are same.
750gb - ext4

  • while connected Rpi 4 over usb3 :
    Writing : 15mb/s
    Reading : 80mb/s

  • while connected Windows over usb3 :
    Writing : 15mb/s
    Reading : 80mb/s

120gb - ext4