EMC Symmetrix DMX-3

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EMC Symmetrix DMX-3 Product Guide
Performance and Optimization
Tiered Storage Optimization
Enginuity 5772 provided two new SW offerings that improve the
ability of organizations to store multiple tiers of data in a single
Symmetrix, isolating cache resources and prioritizing I/O to ensure
more predictable performance levels for different applications:
◆ Symmetrix Priority Controls
◆ Dynamic Cache Partitioning
Symmetrix Priority
Controls
Symmetrix Priority Controls is an offering of 5772 that allows
customers to modify the read I/O performance of devices configured
in the Symmetrix in order to support preferential processing for
specified application tiers with tiered storage in the array. The ability
to control a device’s read priority is delivered using the following
mechanisms:
◆ Prioritization — Ability to prioritize I/O by the Symmetrix device
number. Devices can be grouped for ease of management.
◆ Priority queues — Globally set and execute prioritization of
queue resources by cache, director, and RDF I/O queue. There are
16 priority service levels (1 fastest to 16 lowest). Service levels are
set per group of LUNs. The priority is set at the device level. Each
level represents a time to become urgent value. The higher the
priority level, the shorter the time to become urgent and the faster
the read I/O processing will occur.
◆ Mainframe integration — Supports full integration with IBM’s
Workload Manager for z/OS, responding to WLM commands.
◆ Performance and statistics reporting — The CE is able to control
and query the behavior of the DMX-3 using internal functions. A
new range of counters and statistics allows verification that
Symmetrix Priority Controls is working as expected. These
counters are grouped into three categories:
• Statistics (general/global system statistics)
• Priority statistics
• Device statistics
• Symmetrix Management Console provides intuitive graphical
controls and monitoring for Symmetrix Priority Controls.
Priority Controls also can be managed and monitored using
SymmCLI commands.