Slow drive speeds in Windows VM


New Member
Oct 27, 2023
Hello all,

I'm fairly new to Proxmox, I have a VMware VCP-DCV. Currently looking at trying to switch to Proxmox in my home environment to be able to take advantage of being able to make ZFS storage instead of having to use a hardware RAID controller. My current test server is an R720, dual xeon 2.0GHZ 8/16, 128GB memory, Proxmox installed on a ZFS mirror using two 64GB M.2 drives installed in PCIe cards. So my first testing was done using an H710 hardware raid controller with two 146GB SAS drives in raid 1 for the os, and 6 900GB 10K sas drives in a raid 6 for vm storage. With that configured only getting about 350MB/s disk read speed on the vm storage array. That's when I said hell with it, "rebuilt" the server using the two 64GB m.2 ssd in zfs mirror for os, a single 1TB nvme gen 3 drive for vm storage, and a 8 disk enterprise SSD ZFS pool (tried RAID10 first then RAIDZ2). On the 1TB NVME, getting about the same speeds, maybe a little faster, down to like 160MB/s on the 8 drive ZFS pool. Changed the drive sync to writethrough, made it a little faster but not what I would think this pool should be capable of. So I made an iSCSI connection to my TrueNAS, get about the same 400ishMB/s read speeds. This same iSCSI connection in vmware gets over 1GB/s read. Like I said, i'm fairly new to Proxmox and this is my second time trying to see if this will be a viable replacement for VMware.


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