Question about the VM datastore location and the VM swap file location.
I've tried to install several Linux based VMs under ESXi running on the Mac Mini's 6,2 (Late 2012) internal drive, and it seems that the performance of every VM degrades dramatically when several VMs are running concurrently. The VMs I use are based on Redhat Enterprise Linux 5, but I also have an OS X Mountain Lion VM running OS X Server as well as a Windows 8 VM. When I installed same VMs on an iSCSI target (a RAID NAS with iSCSI target enabled), it appears that VM performance does not degrade much with several VMs (about 6) running concurrently. Have others notice this performance hit when VMs are installed on the datastore on the internal drive?
I've also noticed that the average read latency from the iSCSI storage path is about 8.41 ms (with all VMs located on the iSCSI datastore), whereas the read latency from the storage path on the internal drive of Mac Mini 6,2 is 15.017 ms (without any VMs installed on the internal drive datastore). On the other hand, the average write latency to the iSCSI storage path is 33.04 ms, whereas the average write latency to the internal drive storage path is 13.69 ms.
Second question is about the location of the guest swap files. By default, the location of each VM's swap file is on the same datastore where the VM is installed. So, in my current environment - because every VM is on the iSCSI datastore - the swap files are also on the iSCSI datastore. Would it be beneficial to move these swap files to the Mac Mini 6,2 internal drive?