Storage Target Session Allocation Across Exclusive-Access Fibers

Solution Overview

Problem

Conventional cloud storage systems face inefficiencies in allocating fibers for exclusive access to logical unit numbers (LUNs), leading to CPU core workload imbalances and potential data corruption due to indiscriminate fiber allocation without considering reservation types and workload expectations.

Innovation Solution

A method that involves receiving reservation requests, identifying exclusive access policies, and using a LUN mapping database to realign fibers, ensuring that exclusive type network paths are reserved for initiators with exclusive access requests, while logging out other initiators to prevent data corruption and improve performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If fibers are allocated indiscriminately without considering reservation types, then fiber allocation speed is improved, but CPU core workload imbalance and data corruption occur

Engineering Contradiction:

Improvefiber allocation speedVSAvoiddata integrity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system performs preliminary classification of reservation requests into exclusive and non-exclusive types before fiber allocation. By determining the reservation type in advance and pre-aligning fibers accordingly, the system avoids subsequent workload imbalances and data corruption while maintaining efficient allocation speeds.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Different fibers are assigned different access policies based on their allocation history and current reservations. Exclusive fibers are allocated only to exclusive reservations, while non-exclusive fibers can serve multiple initiators. This local differentiation ensures data integrity on exclusive paths while maximizing resource utilization on shared paths.

Inventive Principle:

Principle #3Local quality

2Adaptability or versatility

If fibers are allocated without considering access types, then resource utilization is improved, but workload imbalance across CPU cores occurs

Engineering Contradiction:

Improveresource utilizationVSAvoidCPU core workload balance

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

The system performs preliminary classification of reservation requests into exclusive and non-exclusive types before fiber allocation. By determining the reservation type in advance and pre-aligning fibers accordingly, the system avoids subsequent workload imbalances and data corruption while maintaining efficient allocation speeds.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Different fibers are assigned different access policies based on their allocation history and current reservations. Exclusive fibers are allocated only to exclusive reservations, while non-exclusive fibers can serve multiple initiators. This local differentiation ensures data integrity on exclusive paths while maximizing resource utilization on shared paths.

Inventive Principle:

Principle #3Local quality

3Adaptability or versatility

If exclusive access paths are not reserved, then fiber allocation flexibility is improved, but data corruption risk increases

Engineering Contradiction:

Improvefiber allocation flexibilityVSAvoiddata corruption risk

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The system performs preliminary classification of reservation requests into exclusive and non-exclusive types before fiber allocation. By determining the reservation type in advance and pre-aligning fibers accordingly, the system avoids subsequent workload imbalances and data corruption while maintaining efficient allocation speeds.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Different fibers are assigned different access policies based on their allocation history and current reservations. Exclusive fibers are allocated only to exclusive reservations, while non-exclusive fibers can serve multiple initiators. This local differentiation ensures data integrity on exclusive paths while maximizing resource utilization on shared paths.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS12450174B2Allocating sessions associated with exclusive access to different fibers of a storage target

Publication Date: 2025.10.21 INTERNATIONAL BUSINESS MACHINE CORPORATION

AI summary

A computer-implemented method, according to one embodiment, includes receiving, from a plurality of initiators, a plurality of reservation requests for logical unit numbers (LUNs) of a storage target. Exclusive type network paths between the initiators and the LUNs requested in the reservation requests are caused to be added to a restricted path list. The method further includes determining the initiators of the plurality of initiators, that have access to at least one of the exclusive type network paths in the restricted path list. Session logout commands are caused to be sent to the determined initiators. The session logout commands instruct the determined initiators to thereafter re-log in to sessions that are logged out of as a result the determined initiators adhering to the session logout commands. The method further includes allocating a first session that a first of the determined initiators re-logs in to, to a first fiber.