I am running Arch 5.1.15 and I have been playing around with Samba today and making some performance discoveries. Thought you might be of help.
These are the specs:
TR 2920x - ASRock X399 Taichi
32GB quad channel RAM
Intel X520 10Gb NIC
Win 10 VM with SR-IOV VF from the Intel X520 NIC. Networking is done through the X520 by the VF passthrough.
FreeNAS 11.2 U4
Dell R710 - Dual E5620 Xeons
4x 10TB WD White in stripe of mirrors
128GB of RAM
Standard Broadcom 1Gb NIC
Switch: Mikrotik CSS326
Up until this point, I was mounting the FreeNAS Samba share from KDE’s Dolphin. I was running a single 8TB WD and I was getting read speeds of ~76MB/s.
I thought it was normal because the link is only GbE and the 8TB drive was over 85% full.
Today I finally completed the switch from the 1x 8TB to the 4x 10TB pool.
I was getting the same numbers.
Windows meanwhile gets 111MB/s reads/writes which is what is normally expected.
I then tried mounting the shares through fstab and lo and behold, my network transfer speeds rose to 111 - 112MB/s. Until I disabled write caching… (Those are numbers I measured at the NIC, Dolphin reports speeds of 1.1GB/s+ due to the caching)
When mounting the SMB share without caching (cache=none option), performance drops to 62MB/s. I don’t get why performance drops since everything in the chain (NVME, HDDs, NICs, network) clearly supports speeds of 112MB/s+.
Does anyone know why this happens? Can it be remedied? I don’t like write caching to network devices.