Modular service level objective (slo) subsystem for a network storage system

A processing system, comprising:

• a processor;
• a memory coupled to the processor;
• an interface configured to communicate with an arbitrary number of external components, each of which is designed to evaluate a different category of configuration state in relation to any arbitrary SLO;
• and
• an SLO engine operatively coupled to, but functionally distinct from, at least some of the external components, to provide to each of the coupled external components SLO data indicating a desired SLO for the data storage system and state data representing a current state of data stored in the data storage system, to receive from each of the coupled external components a separate output that includes a proposed layout and an SLO value associated with the proposed layout.

A method, comprising:

• providing, to each of multiple functional modules, service level objective (SLO) data indicative of a specified SLO for a data storage system, at least some of the functional modules corresponding to a different one of multiple categories of configuration state, at least some of the functional modules configured to apply the SLO data to a function that represents a particular relationship between an SLO characteristic and the corresponding category of configuration state, wherein at least some of the functional modules are configured with the category of configuration state, but without the SLO, and are configured to evaluate a measurement of the category of configuration state in relation to any arbitrary SLO;
• receiving from at least some of the functional modules an output set that includes a layout for the data storage system and an indication of a category of configuration state to which the layout will satisfy the specified SLO;
• and
• selecting a layout to apply to the data storage system based on the output sets from multiple functional modules.