Windows 10: VM - run on SSD or Spinner?
Normally (assuming Windows Host with Linux Guest) the Windows system will manage the I/O for the GUEST so each time the GUEST wants to do an I/O the Windows HOST (running the VM program in this case VMware workstation etc) will intercept the GUEST's I/O request and then translate it into something Windows can do - translate to NTFS for example and then do writes or reads to the Windows Virtual Disks.
That's why for a lot of cases it's far better to pass RAW (un-initialized) Disks to the GUEST (in Windows mark them as offline) if you have complete HDD's available -- especially useful if your GUEST is running as a media or file server.
That way the VM will use NATIVE I/O which - given modern kernels will be far superior with Guest Linux VM's than intercepting and translating say an EXT4 file I/O request into a Windows NTFS one and writing it to a Windows Virtual Disk (vdmk etc).
You can speed up Linux guest I/O's humungously from Windows Hosts especially using VMWARE products -- clear the HDD's out -- on windows DISKPART, CLEAN and then format the clean RAW HDD's in your Linux guest and use mdadm as software RAID on the Guest.
Ensure HDD's OFFLINE to Windows and in the VMware VM config set HDD's as physical discs.
The only thing I can say after reading all the post for this thread is my windows 7 VM runs very well (no problems, and quite fast on the ssd that also contains the OS for the computer.
It depends of course on what you actually USE the VM('s) for and whether you use the HOST significantly or not.
About the only time I use the main Windows 10 Pro HOST is for Ms Office which still IMO has no serious competitor anywhere - especially if you want a decent email package included in the mix - other types of "webmail services" IMO are hideous and often have problems if you have several accounts - and several email servers e,g work, home, your own domain etc etc.
I run a Linux VM server as a NAS box for basic file serving /backups/ multimedia (PLEX / BOSE / SQUEEZEBOX) which work absolutely fine with 4 HDD's as 2 RAID 0 arrays of 9TB and 7TB each.
I also run an XP (modified W2K3 server) VM for a small business (mine) -- creating VINYL recordings for people from CD's or their own music files. The hardware cutting system is old and will only run on XP -- still works fine so I don't need to spend loads of dosh on a new system (these days probably 50 grand (EUR / USD).
My W10 system runs from an SSD, and I boot up the Linux VM's from an internal Micro SD card - the Linux Vm's are pretty well 100% in RAM so once booted there's almost ZERO I/O (from the OS) - so putting it on to the SSD is essentially a bit of a waste in my case. The server VM very rarely ever gets booted so boot time from the Micro SD card is not an issue. 64GB Micro SD card comfortably holds the OS for both CENTOS 7 and XP VM's
I can't say any of the clients (up to 6 at a time) have had any problems with running streamed video / audio from the server or accessing shared files.
@cereberus -- vmware workstation allows VM's to run in BATCH if you want I.e it's almost a "vmserver".
As for I/O as I've said in previous posts if you can use entire HDD's (spinners) for the VM - use in RAW mode which will speed up I/O considerably -- especially on Linux systems as Windows doesn't need to intercept the Linux file system I/O and translate it to vdmk format before performing the write. The linux system will manage it's own I/O.
Just share those disks with Windows by using SAMBA. My XP VM shares the HDD's with the linux VM as well for data files. Data transfer is via CIFS (previously called smbfs and is now much faster) and works very well over networks whether hard wired or accessed via wifi. For a client accessing media streams a decent 1080p video stream will work fine on wifi - you only need to get an average of around 12 Mib/s (megaBITS) to service the video - I think with a 5GHZ wifi you can actually get about 50 Mb(BYTES) / sec. On a Lan - no probs whatsoever.
There's a lot of myths about I/O on VM's -- as always it depends on what you want your VM's to do - but if using regularly with several clients accessing them then using Native I/O will always be better than letting the vmware or hyper-V hypervisor handle it.
Of course if people are running from laptops etc then it probably does make sense to run the whole kybosh from SSD's --it 100% depends on what you use HOST and VM's for of course.
I'm in the process of downloading Win 10 latest ISO. Can it be installed on an eSATA spinner HD as standalone, or must it be installed over existing OS such as Vista, 7 or 8?