SAN Switch Buffer Credit Starvation Load Simulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for testing loaded SAN switches are inadequate, as they either require numerous servers and storage devices or dedicated testing equipment, making it difficult to simulate a large network load effectively and identify potential issues such as frame dropping and timing alterations.
Innovation Solution
The method involves restricting the buffer utilization in a SAN switch by limiting the usable storage space and emulating a large SAN load by buffering frames, using a Buffer Credit Starvation Indicator and Percent of Buffer Utilization Indicator to simulate a stressed environment without the need for extensive resources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a large number of servers and storage devices are added to produce adequate load, then the load on SAN switches increases, but the complexity and cost of the test environment increases
Solution Approach 1:
The patent uses buffer credit starvation to create a simulated copy of high-load conditions. Instead of physically adding numerous servers and storage devices, the invention replicates the effects of heavy load by intentionally starving buffer credits, thereby producing the same stress on SAN switches without requiring a complex test environment with many actual devices.
Solution Approach 2:
The invention changes the buffer credit parameter from its normal state to a starved state. By modifying the buffer credit allocation parameters and intentionally creating buffer credit starvation conditions, the system transforms normal operating conditions into stressed conditions that simulate high load without requiring actual high load from multiple devices.
2Quantity of substance
If dedicated testing equipment is used to produce load port by port, then the load can be controlled, but the complexity and cost of the testing setup increases
Solution Approach 1:
Instead of using dedicated testing equipment to physically generate load, the patent copies the effect of load by manipulating buffer credit parameters. The buffer credit starvation mechanism replicates the stress that would be produced by actual traffic load, eliminating the need for complex dedicated testing hardware while achieving the same testing objectives.
Solution Approach 2:
The SAN switch itself generates the testing conditions through its own buffer management mechanisms. By configuring the switch to operate under buffer credit starvation conditions, the system uses its inherent resources and operations to create the stressed state, rather than requiring external dedicated testing equipment to impose load from the outside.
3Device complexity
If buffer space is restricted to emulate load, then the testing resources required decrease, but the accuracy of simulating real load conditions may be affected
Solution Approach 1:
The patent changes the buffer credit parameter to create starvation conditions that accurately reflect the behavior of switches under high load. By adjusting the buffer credit allocation parameters and creating controlled starvation, the invention maintains measurement precision because it targets the actual parameter (buffer credit availability) that determines switch behavior under load, rather than merely restricting physical buffer space.
Solution Approach 2:
The invention uses feedback from the buffer credit starvation indicator to monitor and maintain accurate simulation conditions. The system continuously monitors buffer credit levels and uses this feedback to ensure that the simulated load conditions remain accurate and representative of real high-load scenarios, thereby maintaining measurement precision while using fewer testing resources.
Data Source
AI summary
Buffer credits are starved upon a storage area network (SAN) switch. The starved buffer credit restricts a SAN switch buffer and enables a smaller load to stress the SAN switch, effectively emulating a larger load. Credit starvation may partially inhibit a SAN switch from delivering frames resulting in the filling of the SAN switch buffer and corresponding computational stress. The emulated load allows for all ports of a SAN switch to be simultaneously tested without the need or expense of a large number computing devices stressing the SAN. The SAN switch may be located within a test SAN environment or may be located in a functioning SAN environment to determine SAN bottlenecks prior to critical loading.