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diff --git a/share/doc/papers/sysperf/7.t b/share/doc/papers/sysperf/7.t new file mode 100644 index 0000000..68f5717 --- /dev/null +++ b/share/doc/papers/sysperf/7.t @@ -0,0 +1,164 @@ +.\" Copyright (c) 1985 The Regents of the University of California. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)7.t 5.1 (Berkeley) 4/17/91 +.\" +.ds RH Conclusions +.NH +Conclusions +.PP +4.2BSD, while functionally superior to 4.1BSD, lacked much of the +performance tuning required of a good system. We found that +the distributed system spent 10-20% more time in the kernel than +4.1BSD. This added overhead combined with problems with several +user programs severely limited the overall performance of the +system in a general timesharing environment. +.PP +Changes made to the system since the 4.2BSD distribution have +eliminated most of the +added system overhead by replacing old algorithms +or introducing additional cacheing schemes. +The combined caches added to the name translation process +reduce the average cost of translating a pathname to an inode by more than 50%. +These changes reduce the percentage of time spent running +in the system by nearly 9%. +.PP +The use of silo input on terminal ports only when necessary +has allowed the system to avoid a large amount of software interrupt +processing. Observations show that the system is forced to +field about 25% fewer interrupts than before. +.PP +The kernel +changes, combined with many bug fixes, make the system much more +responsive in a general timesharing environment. +The 4.3BSD Berkeley UNIX system now appears +capable of supporting loads at least as large as those supported under +4.1BSD while providing all the new interprocess communication, networking, +and file system facilities. +.nr H2 1 +.ds RH Acknowledgements +.SH +\s+2Acknowledgements\s0 +.PP +We would like to thank Robert Elz for sharing his ideas and +his code for cacheing system wide names and searching the process table. +We thank Alan Smith for initially suggesting the use of a +capability based cache. +We also acknowledge +George Goble who dropped many of our changes +into his production system and reported back fixes to the +disasters that they caused. +The buffer cache read-ahead trace package was based +on a program written by Jim Lawson. Ralph Campbell +implemented several of the C library changes. The original +version of the Internet daemon was written by Bill Joy. +In addition, +we would like to thank the many other people that contributed +ideas, information, and work while the system was undergoing change. +.ds RH References +.nr H2 1 +.sp 2 +.SH +\s+2References\s-2 +.LP +.IP [Cabrera84] 20 +Luis Felipe Cabrera, Eduard Hunter, Michael J. Karels, and David Mosher, +``A User-Process Oriented Performance Study of Ethernet Networking Under +Berkeley UNIX 4.2BSD,'' +Research Report No. UCB/CSD 84/217, University of California, +Berkeley, December 1984. +.IP [Cabrera85] 20 +Luis Felipe Cabrera, Michael J. Karels, and David Mosher, +``The Impact of Buffer Management on Networking Software Performance +in Berkeley UNIX 4.2BSD: A Case Study,'' +Proceedings of the Summer Usenix Conference, Portland, Oregon, +June 1985, pp. 507-517. +.IP [GADS85] 20 +GADS (Gateway Algorithms and Data Structures Task Force), +``Toward an Internet Standard for Subnetting,'' RFC-940, +Network Information Center, SRI International, +April 1985. +.IP [Joy80] 20 +Joy, William, +``Comments on the performance of UNIX on the VAX'', +Computer System Research Group, U.C. Berkeley. +April 1980. +.IP [Kashtan80] 20 +Kashtan, David L., +``UNIX and VMS, Some Performance Comparisons'', +SRI International. February 1980. +.IP [Lankford84] 20 +Jeffrey Lankford, +``UNIX System V and 4BSD Performance,'' +\fIProceedings of the Salt Lake City Usenix Conference\fP, +pp 228-236, June 1984. +.IP [Leffler84] 20 +Sam Leffler, Mike Karels, and M. Kirk McKusick, +``Measuring and Improving the Performance of 4.2BSD,'' +\fIProceedings of the Salt Lake City Usenix Conference\fP, +pp 237-252, June 1984. +.IP [McKusick85] +M. Kirk McKusick, Mike Karels, and Samual Leffler, +``Performance Improvements and Functional Enhancements in 4.3BSD'' +\fIProceedings of the Portland Usenix Conference\fP, +pp 519-531, June 1985. +.IP [Mockapetris83] 20 +Paul Mockapetris, ``Domain Names \- Implementation and Schedule,'' +Network Information Center, SRI International, +RFC-883, +November 1983. +.IP [Mogul84] 20 +Jeffrey Mogul, ``Broadcasting Internet Datagrams,'' RFC-919, +Network Information Center, SRI International, +October 1984. +.IP [Mosher80] 20 +Mosher, David, +``UNIX Performance, an Introspection'', +Presented at the Boulder, Colorado Usenix Conference, January 1980. +Copies of the paper are available from +Computer System Research Group, U.C. Berkeley. +.IP [Nagle84] 20 +John Nagle, ``Congestion Control in IP/TCP Internetworks,'' RFC-896, +Network Information Center, SRI International, +January 1984. +.IP [Ritchie74] 20 +Ritchie, D. M. and Thompson, K., +``The UNIX Time-Sharing System'', +CACM 17, 7. July 1974. pp 365-375 +.IP [Shannon83] 20 +Shannon, W., +private communication, +July 1983 +.IP [Walsh84] 20 +Robert Walsh and Robert Gurwitz, +``Converting BBN TCP/IP to 4.2BSD,'' +\fIProceedings of the Salt Lake City Usenix Conference\fP, +pp 52-61, June 1984. |