Speaker
Dr
Wenji Wu
(Fermi National Accelerator Laboratory)
Description
The computing models for HEP experiments are becoming ever more globally distributed
and grid-based, both for technical reasons (e.g., to place computational and data
resources near each other and the demand) and for strategic reasons (e.g., to
leverage technology investments). To support such computing models, the network and
end systems (computing and storage) face unprecedented challenges. One of the biggest
challenges is to transfer physics data sets – now in the multi-petabyte
range and expected to grow to exabytes within a decade – reliably and efficiently
among facilities and computation centers scattered around the world. Both the network
and end systems should be able to provide the capabilities to support high bandwidth,
sustained, end-to-end data transmission. Recent trends in technology are showing that
although the raw transmission speeds used in networks are increasing rapidly, the
rate of advancement of microprocessor technology has slowed down over the last couple
of years. Therefore, network protocol-processing overheads have risen sharply in
comparison with the time spent in packet transmission, resulting in the degraded
throughput for networked applications. More and more, it is the network end system,
instead of the network, that is responsible for degraded performance of network
applications. In this paper, the Linux system’s packet receive process is studied
from NIC to application. We develop a mathematical model to characterize the Linux
packet receive process. Key factors that affect Linux systems’ network performance
are analyzed.
Primary author
Dr
Wenji Wu
(Fermi National Accelerator Laboratory)
Co-author
Dr
Matt Crawford
(Fermi National Accelerator Laboratory)
