Receiver-Driven Rendezvous Scheduling for Incast Congestion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high-performance computing environments, incast congestion in networks due to many-to-one data transfers leads to reduced throughput and resource-intensive packet reordering mechanisms, exacerbated by out-of-order packet arrivals and lossy networks.
Innovation Solution
Implementing a receiver-driven incast management system that schedules data retrieval based on network congestion levels, using Remote Direct Memory Access (RDMA) to control data arrival and reduce conflicts, and integrates with credit-based systems to manage congestion thresholds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If many-to-one data transfers are performed in high-performance computing networks, then data retrieval efficiency is improved, but network congestion occurs leading to reduced throughput
Solution Approach 1:
The system performs preliminary actions by having the receiver device proactively schedule and initiate data retrieval operations before the sender device is ready to transmit. The receiver device creates retrieval schedules, sets up buffer allocations, and prepares RDMA operations in advance, controlling the timing and pace of data transfers to prevent network congestion while maintaining high retrieval efficiency.
2Reliability
If packet reordering mechanisms are implemented to handle out-of-order arrivals, then data delivery reliability is improved, but resource consumption increases
Solution Approach 1:
The system inverts the traditional approach by having the receiver device control the data retrieval process through scheduled RDMA operations, rather than having the sender device push data. This inversion eliminates the need for complex packet reordering mechanisms at the receiver, as data is retrieved in a controlled sequence that prevents out-of-order arrivals, thereby maintaining reliability while reducing resource consumption.
3Loss of energy
If receiver-driven scheduled data retrieval is implemented, then network congestion is reduced, but system complexity increases
Solution Approach 1:
The receiver device performs self-service by autonomously managing its own data retrieval schedule, buffer allocations, and RDMA operation timing. It independently monitors network conditions, adjusts retrieval rates, and controls the pace of data transfers without requiring complex coordination protocols with sender devices, thereby reducing network congestion while keeping system complexity manageable.
Data Source
AI summary
A network interface controller (NIC) facilitating incast management at a computing system is provided. During operation, the NIC can receive, via a network, a request to send data from a remote computing system. The NIC can determine that the request is among a plurality of requests from a plurality of remote computing systems accessible via the network. Based on a descriptor in the request, the NIC can determine a storage location of the data at the remote computing system. The NIC can then determine a level of congestion associated with the plurality of requests at the computing system. The NIC can schedule a data retrieval in response to the request based on the level of congestion and with respect to the plurality of requests. The NIC can then retrieve the data from the storage location based on remote access.