ASQ : application specific network queues

Details

Supervisors

Tom Barbette

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] en sciences informatiques, à finalité spécialisée

Abstract

Each Network Interface Cards (NIC) use a proprietary format to inform the host about the arriving packets, called the packet descriptor. This is one of the reasons why each NIC comes with a different driver, as a different software is needed to transform the custom format into a standard descriptor format that the kernel understands. As it has been shown by previous work, this transformation is costly. It throws away some precious instruction cycles and wastes CPU caches. At the same time, applications may not need this "generic" format resulting from the transformation and would benefit from a custom format. This thesis presents an optimization done on the management of the packet's descriptor. Using the NVIDIA Mellanox BlueField-2, a programmable Network Interface Card, we will modify each descriptor associated with the received packets and will format it to fulfill the needs of an application running on the main CPU. This will bring two major advantages. Firstly, the unused data from the descriptor will be removed to reduce its size and thus optimize the cache usage, leading to better memory management. Secondly, specific fields required by the application will be added to the descriptor. By offloading this process to the NIC it will free some computation power on the host. When comparing the performance of a standalone host application, which involves payload analysis, to the same application running with the help of the ASQ model application (the software developed during this thesis) on the SmartNIC, we noticed a significant improvement in throughput. Specifically, for 64 bytes packets, there was an observed increase in throughput of up to 38%. we also profiled the CPU utilization of the host system, and noticed a decrease in CPU cycle consumption up to 70%, freeing the CPU resources.