Cache and TLB Effectiveness in the Processing of Network Data

Michael A. Pagels
Peter Druschel
Larry L. Peterson1

TR 93 04

Abstract

This paper considers the question of how effective caches are in processing network I/O. Our analysis shows that operating system structure plays a key role in the caches behavior, with BSD Unix (a monolithic OS) making more effective use of the cache than Mach (a microkernel OS). Moreover, closer inspection shows that several factors contribute to this result, including how TLBs are managed, how scheduling points are interspersed with data accesses, how data is laid out in memory, and how network functionality is distributed between user space and the kernel.

March 9, 1994

Department of Computer Science
The University of Arizona
Tucson, AZ 85721

1This work supported in part by National Science Foundation Grants CRC-9102040,NCR-9204390,ARPA Contract DABT63-91-C-0030 and the Hewlett-Packard Company.