Hello - I currently have a 2011 Macbook Pro 13" 2.3GHz i5 with 16GB RAM and 2 Solid State drives. I run my Parallels instances off the 2nd hard drive and this configuration seems to work great. I am considering upgrading to a 15" i7 2.3GHz 16GB RAM, but I see that the new 15" MBPs don't have room to easily install a 2nd hard drive. My question is... how much will performance be affected if I install my VMs on my primary (SSD) hard drive? Will I gain enough by moving to an i7 to offset this performance degradation? Thanks in advance
The CPU won't affect the performance, the difference between running two separate drives or just one is with concurrent I/O requests, from OS X and from the Guest VM, and that will be be the bottleneck, of sharing the bandwidth of one SSD interface. You'll only hit this bottleneck when you are running I/O intensive apps on both the Host and the Guest, that's where separate drives makes a difference. However, the important difference between the older model and the newer is the PCIe-based SSD which is faster than the SATA interface, that's the thing that will probably actually make up the performance loss under certain loads.
