Explaining NUMA Spanning in Hyper-V

NUMA Spanning or Non-Uniform Memory Address Spanning was a feature introduced into motherboard chipsets by Intel and AMD. Intel implemented it with the feature set Quick Path Interconnect (QPI) in 2007 and AMD implemented it with HyperTransport in 2003. NUMA uses a construct of nodes in it’s architecture. As the name suggests, NUMA refers to system memory (RAM) and how we use memory and more specifically, how we determine which memory in the system to use.

Slow WDS PXE Clients and Bad Memory

The machines in question were all configured with 6144MB of RAM in the form of three 2GB DIMMs. What we didn’t notice at an early stage and why would you, was that some of the machines exclusively had three DIMMs of HP certified Micron memory in them however it transpires that our faulting machines had a combination of HP certified Micron memory and Hynix HP certified memory.

Cisco ASA 5520 Memory Upgrade

For anyone using a Cisco ASA 5505, 5510, 5520 or 5540 in their home, lab or non-production environments and wants to be able to run ASA OS versions 8.3 and later you’re probably going to be on the market for a memory upgrade. Cisco ASA memory upgrades are bonkers expensive and while for a production environment you’d want to pay this to get the Cisco TAC support, chances are you aren’t going to want to stump up this kind of money for other purposes.