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6.5 Disk Magic Easy Tier modeling
Disk Magic supports DS8000 Easy Tier modeling for DS8800 and DS8700 multi-tier
configurations. The performance modeling that is provided by Disk Magic is based on the
workload
skew level concept. The skew level describes how the I/O activity is distributed
across the capacity for a specific workload. A workload with a low skew level has the I/O
activity distributed evenly across the available capacity. A heavily skewed workload has many
I/Os to only a small portion of the data. The workload skewing affects the Easy Tier
effectiveness, especially if there is a limited ...