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.
Maybe you want to test the performance of your HDD first. My suggestion is to connect your HDD to your Laptop and perform the following tests and then do the same for the Raspi. So you can get a first picture about the speed and a comparison between Laptop and Raspi. In the following commands, please replace
/dev/sdawith your actual device.Test with cache:
sudo hdparm -tT /dev/sdaTest without cache:
sudo hdparm -tT --direct /dev/sdaTaken from here [German]
(sorry have accidentely deleted my post)
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.