1 Reply Latest reply on Feb 15, 2017 10:33 AM by Loobster

    Why is ESXi so slow with an SSD?

    Loobster Lurker

      Hi all, first post here.

       

      I have a lab computer at the house for learning and working with ESXi. Currently running 6.5. It's an older but still powerful tower, i7-2600k, 32GB RAM. I was using a 2TB HDD for ESXi but found it a bit slow, so purchased an SSD (Crucial MX300, 525GB). I reinstalled 6.5 from scratch onto the SSD as the only storage in the computer.

       

      But now I am finding that this SSD is much slower in performance with ESXi than the regular spinny hard drive was. Trying to migrate VMs from Workstation 12 to ESXi 6.5 over my gigabit network is painfully slow. It was kinda slow with the HDD but is way slower with the SSD.  I have also attempted to create a new VM using a Windows 10 x64 ISO that is in the datastore. This process was also very slow. It took about 40 minutes on the "Getting files ready for installation" stage. I would have expected that to be done in less than 5 minutes. I checked and CPU and RAM are at very low usage levels yet the VM creation is dragging horribly. Somehow ESXi's interaction with the SSD is crazy slow.

       

      I have two NICs in the machine, an on-board Intel 82579v, but to rule out problems with that, I also purchased an Intel CT Gigabit PCI express adapter which is widely regarded as very compatible with all recent versions of ESXi. no change to the speed.

       

      So here's what I've tried so far:

       

      Checked in Storage that ESXi is recognizing the device as an SSD (it is).

      Tried both NICs, no difference between the two

      Tested creating a VM on the host with the only traffic going off the box being to my instance of VMware workstation 12 on my main PC, for control/monitoring only. VERY slow.

       

      I've looked through the forums and there isn't much about SSDs so I am hoping that someone who has come up against this issue and overcome it can tell me what's wrong here.

       

      Thanks!

        • 1. Re: Why is ESXi so slow with an SSD?
          Loobster Lurker

          After much more searching, this was the answer:

           

          Very slow speed on SSD

           

          After running this command and rebooting the ESXi box, speed is very fast with creating a VM on the ESXi host. Upload from Workstation is still not as fast as I'd like, but maybe that process is never very fast.  But the VM (only 9.0GB in size) that looked like it was going to take about 10 hours yesterday before I cancelled it, looks like it will take less than half an hour today.