Switch Queue Control Using Reference PFC Counters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Switches without PFC counters are unable to detect PFC storms, leading to potential congestion and link collapse.
Innovation Solution
A method and apparatus that utilize a reference switch with a PFC counter to monitor and control message queues on target switches without PFC counters by transmitting control instructions to manage message discarding or retaining based on PFC pause frame quantities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If switches are deployed without PFC counters to reduce costs, then device cost is reduced, but the ability to detect PFC storms is lost
Solution Approach 1:
The patent introduces an intermediary mechanism where a neighboring switch with PFC counter functionality acts as a detector for the switch without PFC counters. The detector switch monitors PFC pause frames transmitted between the target switch and its upstream neighbor, effectively providing PFC storm detection capability to switches that would otherwise lack this functionality. This resolves the contradiction by enabling cost-effective deployment while maintaining reliability through the intermediary detection mechanism.
2Reliability
If PFC counters are deployed on all switches to enable PFC storm detection, then PFC storm detection capability is improved, but device cost increases
Solution Approach 1:
The patent makes the detector switch perform multiple functions: it acts as a normal forwarding switch for regular traffic while simultaneously functioning as a PFC storm detector for its downstream neighbor. This multi-functionality eliminates the need for every switch to have dedicated PFC counter hardware, as the detector switch's PFC counter serves both its own needs and those of its downstream neighbor, thereby reducing overall device cost while maintaining detection capability.
3Reliability
If the detector switch transmits control instructions to discard messages in target message queue, then queue congestion is prevented, but message loss increases
Solution Approach 1:
The patent applies preliminary anti-action by proactively discarding messages in the target message queue when a PFC storm is detected, before the congestion can propagate and cause link collapse. The detector switch monitors PFC pause frames and, upon detecting storm conditions, immediately transmits control instructions to discard messages in the affected queue. This preemptive action prevents the harmful effect of congestion from spreading, even though it results in controlled message loss at the source.
Solution Approach 2:
The patent converts the harmful effect of message loss into a beneficial outcome by strategically discarding messages only in the specific target message queue affected by the PFC storm, rather than broadly across all queues. The controlled message loss in the affected queue prevents catastrophic link collapse and protects the overall network, transforming what appears to be a negative effect (message loss) into a protective mechanism that saves the broader system.
Data Source
AI summary
Embodiments of the present application provide a switch control method and apparatus, a non-volatile readable storage medium, and an electronic apparatus. The switch control method includes: obtaining a first transmission quantity that is recorded in a priority flow control (PFC) counter in a reference switch and that corresponds to a target message queue; and in a case that the first transmission quantity satisfies a preset first control condition, transmitting a first control instruction to a target switch, where the first control instruction is configured for instructing a discarding operation on a message in the target message queue.