Hello,
I’m in the process of refining my home lab setup and I’ve hit a performance issue that I can’t quite explain.
Current layout:
The issue:
When testing directly inside the TrueNAS VM (local pool), I see expected sequential speeds (900–1000 MB/s read, 600–700 MB/s write).
However, when accessing the same storage over SMB from another 10GbE machine, I’m only getting 350–400 MB/s reads and 250–300 MB/s writes.
Things I’ve already checked:
Appreciate any insight.
I’m in the process of refining my home lab setup and I’ve hit a performance issue that I can’t quite explain.
Current layout:
- Host: Ryzen 7 5700X, 128GB DDR4 ECC UDIMM
- Motherboard: B550 chipset
- Hypervisor: Proxmox VE 8.x
- Storage HBA: LSI 9300-8i (IT mode)
- Pool: 6× 8TB SATA HDD (RAIDZ2)
- Cache: 2× NVMe (mirrored, used as special device + metadata)
- Network: Mellanox ConnectX-3 10GbE (direct attach)
The issue:
When testing directly inside the TrueNAS VM (local pool), I see expected sequential speeds (900–1000 MB/s read, 600–700 MB/s write).
However, when accessing the same storage over SMB from another 10GbE machine, I’m only getting 350–400 MB/s reads and 250–300 MB/s writes.
Things I’ve already checked:
- MTU 9000 enabled on both ends
- Verified 10Gb link is negotiated
- CPU usage during transfer is low (<20%)
- No packet loss or drops on interface
- SMB multichannel disabled (testing simple case first)
- Virtualization overhead
- SMB tuning issue
- ZFS sync / recordsize mismatch
- Something related to Proxmox bridge configuration
Appreciate any insight.
