Pivot Point

Fixed recommendations for consolidation ratios are cancerous.  Whether we are talking about vCPUs per core, virtual machines per host, or VMDKs per LUN, there is no single number the represents the “right” ratio.  Accurate guidance requires workload characterization and fine tuning using vSphere’s performance counters.  Today I want to highlight one experiment that shows application choice impacting VMDK-to-LUN consolidation.  The inescapable conclusion is that sequential access data must be separated from random access files!

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