Configuration change priorities – The Optimizer can do migrations that were defined as rules, swaps that are found by the Optimizer analysis engine in automatic mode, and manual swaps and migrations. The new Optimizer has a priority mechanism to determine which configuration change to invoke when an inclusion swap time window becomes active. Based on this logic, rules of meta migrations get the highest priority once they started; this is in order to accelerate the migration and minimize the time that the metadevice rules are broken (all members on same speed disks). When there is no meta migration in progress then the scheduler will use the rules priorities while the automatic swap suggestions are considered as normal priority,
By default, Optimizer runs in Automatic mode, meaning that when Optimizer determines a swap list, it will schedule the swap to occur at the next available swap time window. (Refer to the section “Swap and Performance Time Windows” on page 24.) However, the user may choose to monitor the swaps before they start by selecting User Approved mode. In User Approved mode, the Optimizer displays the swap list and allows the user to either approve or cancel the swap list via the swap wizard.
The swap wizard also provides other modes of operation: User Defined (allows the user to manually define swaps, migrations) and Rollback (allows the user to undo all swaps done from a specific date and time).
Switching between Automatic and User Approved mode is done through the Optimizer dialog box (Figure 6), with the available swap modes of Automatic and User Approved. If Automatic is selected, Optimizer will perform swaps without user confirmation. If User Approved is selected, Optimizer prompts for approval before each swap session.
Figure 6. Optimizer parameter settings tabs
EMC Symmetrix Optimizer A Detailed Review