I've been using my Pi4 as a NAS for a few months now and with the older 5.4 kernel it was rock solid.
Thanks to XFS I was able to write and read with a constant 112mb/s and max out the interface completely.
However since the 5.10 kernel the performance has degraded quite a lot.
The constant 112mb/s dropped down to around 60-70mb/s and the speed was varying a lot.
At least with the current kernel 5.10.36 the write speed seems to be fine again (112mb/s) but the read speed is still sitting at around 80mb/s.
It might not sound like much, but I have absolutely no explanation for it.
There's no IO delay and the cpu usage is quite low as well.
Does anyone have an idea how to debug this issue or is running into the same thing?
How can the read speed even be lower than the write speed?
My samba config is quite minimal, no special socket options or cache configured.
(Most of those options are outdated anyway and I've made better experiences without them)
I'm running a samba server on my Raspberry PI 4 2GB.
The PI is connected to my workstation and mac via gigabit and has a 250GB Crucial MX500 SSD attached via a USB 3 adapter.
I just did some performance testing by uploading a 5GB file to the samba share.
The performance is very good, although it varies quite a lot.
Sometimes I'm able to max out the interface with around 110MB/s but on the other hand it's often droping to around 70-80mb/s.
Is there a reason for those drops or some way to get a more stable upload speed?
Downloading files from the PI is always at 110MB/s
Same issue here with a PI 4