This is my first time setting up a Raspberry Pi4 (8GB). Before, I have used a RPi 3B for some other things. From what i have read is, that IO performance should be a lot better on the RPi4, as with the RPi3B. But i get the same speeds as before. I have setup the following:
- Installed Raspbian Lite (64bit)
- enabled SFTP/SSH
- Setup a user for SFTP only access, with home on a connected USB HDD
- the USB HDD is connected to one of the USB3 ports
- This is the same setup on the RPi3B
When I now try to start to copy a 2GB file from my Laptop via LAN, i get in both cases a max of 11.6 or 11,5MB/s. But according to articles like this (https://www.jeffgeerling.com/blog/2021/raspberry-pi-25-gbps-16-tb-omv-nas-setup-and-performance), it should be much faster. Is there some secret, or whats the problem?
BTW: The Laptop runs on Manjaro Linux, where i start the transfer, there is no Windows available.
The speed looks fine for me on the Laptop itself:
/dev/sda: Timing cached reads: 28080 MB in 1.98 seconds = 14161.28 MB/sec Timing buffered disk reads: 448 MB in 3.02 seconds = 148.55 MB/sec/dev/sda: Timing O_DIRECT cached reads: 604 MB in 2.00 seconds = 301.42 MB/sec Timing O_DIRECT disk reads: 454 MB in 3.02 seconds = 150.36 MB/secOn the Pi itself i get:
/dev/sda: Timing cached reads: 1974 MB in 2.00 seconds = 988.54 MB/sec Timing buffered disk reads: 196 MB in 3.02 seconds = 64.91 MB/sec/dev/sda: Timing O_DIRECT cached reads: 122 MB in 2.01 seconds = 60.64 MB/sec Timing O_DIRECT disk reads: 194 MB in 3.03 seconds = 64.03 MB/secThis also much above the speed, i got, when i transfer files via SFTP/SCP.
I have tested also iperf and got:
0.0000-10.2100 sec 113 MBytes 93.1 Mbits/secIt seems like this is really somewhere limiting to 100MBit.
It seems the limiting factor is the switch or cable. If i connect the Rpi to the router directly, i get:
0.0000-10.1222 sec 281 MBytes 233 Mbits/secIts the cable. After changing the cable between the Switch and the Router, i got
iperftest up to:0.0000-10.0416 sec 1.09 GBytes 932 Mbits/sec.We had some workmen in the house a few weeks ago. Apparently, they damaged the cable. The test cable was unfortunately too short for permanent use, but it was enough for testing. I now get an upload of 65MB/sec on an average. This is about the same as the limit I had already determined through
hdparmon the RPi4. I don’t know, whyhdparmis faster directly on the laptop, maybe the USB Controller is not the best on the RPi4. But anything is better than 11MB/sec.The situation is different when the laptop is only connected to the network via WiFi. Here I get a maximum of 28MB/sec. I have not yet found a solution how this could be faster.