One of the trends that VMware co-founder Mendel Rosenblum talked about in his keynote at VMworld was the benefits to virtualization of new quad-core processors.
Imagine eight 1u systems, each with a single-core CPU. If one CPU gets busy and you want to balance the load, the system has to use VMotion to move a virtual machine from one processor to another. This is a high overhead operation. If those 8 CPUs have 4 cores each and are put into a single box, now the vmkernel scheduler can do the work — a much lower-cost operation than VMotion — and you have better utilization and even more functionality — for instance, a security virtual machine running on a spare core. You can start dedicating a number of cores to specific workloads. Mendel showed off a very high density system (from Rackable) with 320 cores in a single rack.
Intel’s Sudip Chahal has gotten his hands on some early copies of these quad core chips, and posts some early encouraging words at the new IT@Intel Blog.
Recently Intel launched the industry’s first high-volume quad-core
processor based on the new Core 2 micro-architecture, code named
Clovertown. … Frankly, the entire team is very impressed
at the scaling we are seeing relative to the Woodcrest based servers
(in the 1.5-1.7x range on an average – more about our methodology
later) …While virtualizing test and development systems and other
“low-risk” systems is all well and fine, the price-performance of the
new Clovertown quad-core systems should enable IT to take
virtualization to an entirely new level. Many applications that may not
have been good candidates for virtualization in the past due to
performance concerns or concerns about high costs now all of a sudden
become prime candidates for virtualization and materially help move IT
towards the end-goal of an automated, modular and virtualized compute
utility. While previously it may not have been cost-effective to
“dedicate” a host and expensive virtualization software licenses to
host a modest number of more demanding applications, that is now in the
past. The new very cost-effective quad-core processor based servers
(pricing is comparable to dual-core servers) combined with attractive
socket based licensing policies means that virtualization for the
masses is now an affordable reality.
