
76 DS8800 Performance Monitoring and Tuning
Figure 3-6 DS8000 virtualization hierarchy
3.3 Data placement on ranks and extent pools
It is important to understand how the volume data is placed on ranks and extent pools. This
understanding helps you to decide how to create extent pools and choose the required
number of ranks within an extent pool. It also helps you to understand and detect
performance problems or optimally tweak overall system performance.
It can also help you fine-tune system performance from an extent pool perspective, for
example, sharing the resources of an extent pool evenly between application workloads or
isolating application ...