VMware Large Snapshot Safe Removal

One of the great virtualization and VMware features is the ability to take snapshots of a virtual machine. The snapshot feature allows an IT administrator to make a restore point of a virtual machine, with the option to make it crash consistent. This feature is particularly useful when performing upgrades or testing, as if anything goes wrong during the process, you can quickly go back to a stable point in time (when the snapshot was taken).
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NUMA and vNUMA made simple!

What is NUMA?

Most modern CPU’s, Intel new Nehalem’s and AMD’s veteran Opteron are NUMA architectures. NUMA stands for Non-Uniform Memory Access. Each CPU get assigned its own “local” memory, CPU and memory together form a NUMA node (as shown in the diagram below).

Memory access time can differ due to the memory location relative to a processor, because a CPU can access it own memory faster than remote memory thus creating higher latency if remote memory is required.

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