Posts about memory

vNUMA: What it is and why it matters

In vSphere 5, we introduced vNUMA which allows interested guest operating systems to see that they are running on a NUMA (Non Uniform Memory Architecture) topology. For those not familar, here is a one-diagram NUMA explanation. As you can see, in the UMA case, the cost of accessing a particular memory address is the same […]

Future Memory Technology

Dean Klein, VP of Memory System Development at Micron, gave the Thursday keynote at ISC ’11 last week. He spoke about future memory technologies with an emphasis on what will be required for exacscale HPC systems. I had often heard that memory consumes roughly half the power in a typical system. While I realize that […]

Memory Virtualization and HPC Performance

Jeff Buell in our performance group just posted another excellent HPC performance piece on VROOM. This study examines the effects of memory virtualization on HPL and StarRandomAccess, two HPC benchmarks with very different memory access patterns. The results show that hardware-based memory virtualization does not always lead to the best overall performance, especially with HPC […]