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diff --git a/usr.bin/gprof/PSD.doc/intro.me b/usr.bin/gprof/PSD.doc/intro.me new file mode 100644 index 0000000..3a872b2 --- /dev/null +++ b/usr.bin/gprof/PSD.doc/intro.me @@ -0,0 +1,81 @@ +.\" Copyright (c) 1982, 1993 +.\" 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. +.\" +.\" @(#)intro.me 8.1 (Berkeley) 6/8/93 +.\" +.sh 1 "Programs to be Profiled" +.pp +Software research environments +normally include many large programs +both for production use and for experimental investigation. +These programs are typically modular, +in accordance with generally accepted principles +of good program design. +Often they consist of numerous small routines +that implement various abstractions. +Sometimes such large programs are written +by one programmer +who has understood the requirements for +these abstractions, and has programmed them +appropriately. +More frequently the program has +had multiple authors and has +evolved over time, changing the demands placed +on the implementation of the abstractions without +changing the implementation itself. +Finally, the program may be assembled from a library +of abstraction implementations +unexamined by the programmer. +.pp +Once a large program is executable, +it is often desirable to increase its speed, +especially if small portions of the program +are found to dominate its execution time. +The purpose of the \fBgprof\fP profiling tool is to +help the user evaluate alternative implementations +of abstractions. +We developed this tool in response to our efforts +to improve a code generator we were writing [Graham82]. +.pp +The \fBgprof\fP design takes advantage of the fact that the programs +to be measured are large, structured and hierarchical. +We provide a profile in which the execution time +for a set of routines that implement an +abstraction is collected and charged +to that abstraction. +The profile can be used to compare and assess the costs of +various implementations. +.pp +The profiler can be linked into a program without +special planning by the programmer. +The overhead for using \fBgprof\fP is low; +both in terms of added execution time and in the +volume of profiling information recorded. |