IDF, Intel’s festival for hardware geeks, better known as IDF, was largely overshadowed by some announcements from that not insignificant fruit company from Cupertino. The coincident timing was unfortunate since Intel provided plenty of news for both PC watchers and data center designers. On the server front, the company released a major update to the Xeon line based on the Haswell microarchitecture and as I discuss in this column, the new products includes several enhancements specifically designed to improve performance with virtualized workloads and multi-tenant cloud deployments.
One of the notable changes addresses the bane of many cloud customers: noisy neighbors. Disruptive neighbors are a major problem in any shared environment, whether it’s a cubicle farm, apartment building or cloud service. However unlike the party animal upstairs who regularly keeps you up until the wee hours, in multi-tenant cloud, IaaS environments, you typically don’t know precisely who the noisy tenant is. The only thing for certain is that at least one workload on the same physical server is hogging resources, slowing down everyone else. But wait, isn’t virtualization supposed to solve this? Doesn’t each workload have its own virtual slice of the system, walled off and isolated from every other VM? Of course; but the dirty little secret of virtualization is that the software abstraction only goes so far and there remain several shared resources on every system.
As I detail in the column, the most visible resources hogged by noisy neighbors are network and disk I/O, however these are easy to spot. However another shared element, processor cache memory, has been completely invisible and inaccessible to the hypervisors powering all cloud services: at least until now. Intel, in its new Haswell architecture Xeon E5 v3 processors, just announced at IDF, takes a first step at silencing noisy neighbors at the source, namely the on chip execution environment. Click through for the rest of the story.