I have Proxmox 5.1. Xpenology 1.02b loader; DSM6.1.4 Update 5. Intel onbard (AHCI) SATA controller passthrough. I have 3 SSD in RAID0 mode. What I notice is, the write performance on SSD is terrible. I've try to tweak Proxmox, and the Xpeno VM, but nothing seems to help.
My VM config:
args: -device 'piix3-usb-uhci,addr=0x18' -drive 'id=synoboot,file=/var/lib/vz/images/100/synoboot_jun2b_virtIO.img,if=none,format=raw' -device 'usb-storage,id=synoboot,drive=synoboot'
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