[SOLVED] Virtual machines on HDD & OS on SSD (or vice versa) ?

[71GA]

I have a computer with SSD where OS is installed, but the same disk also keeps my virtual machine images (large .qcow2 files).
It works fine.

Now I wonder... On this computer the installed OS is a really minimal Linux Debian installation with just 4 minimal programs installed.
Could I benefit if I used some old HDD and installed OS there while keeping SSD exclusively for virtual machine images storage?

 

[USAFRet]

Why bother with the HDD at all?

 

[71GA]

This is not the question... But to answer... Out of curiosity.

 

[USAFRet]

This is not the question... But to answer... Out of curiosity.

Well, whatever you're doing would probably be "slower" than if everything were on solid states drives.

What 'benefit' were you thinking it would impart?

 

[71GA]

Well OS would be on a separate disk... So maybee some slight benefit?

 

[USAFRet]

Well OS would be on a separate disk... So maybee some slight benefit?

Would still be slower/less responsive than if all were on one SSD, or the OS on one small SSD and the VMs on another.

 

[alceryes]

Keep them on the SSD. It would be much, much slower, especially when more than one VM got busy with something like updates.

I ran multiple VMs on a WD Black 300GB 10k RPM drive once upon a time. Windows updates was painful.

 

[71GA]

So if I understood correctly performance will suffer even if I use OS on one SSD and VMs on another SSD compared to keeping OS & VMs on the same single SSD!? How come?
If this is true than I really need one of those PCI 4.0 NVMe drives... 7000MB/s is preety good don't you think?

What else would benefit my VM server the most compared to a fast SSD?

 

[USAFRet]

So if I understood correctly performance will suffer even if I use OS on one SSD and VMs on another SSD compared to keeping OS & VMs on the same single SSD!? How come?
If this is true than I really need one of those PCI 4.0 NVMe drives... 7000MB/s is preety good don't you think?

What else would benefit my VM server the most compared to a fast SSD?

No.
2x SSD are better than one. 1 for the OS, 1 for the VM's.
1x SSD is better than HDD + SSD.
PCIe 4.0 drive is of no consequence in this scenario. That "7000MB/s" is for large sequential data. Not small back and forth as the VMs will be doing.