MONCONTROL(3) BSD Library Functions Manual MONCONTROL(3)NAME
moncontrol, monstartup -- control execution profile
SYNOPSIS
moncontrol(int mode);
monstartup(u_long *lowpc, u_long *highpc);
DESCRIPTION
An executable program compiled using the -pg option to cc(1) automatically includes calls to collect statistics for the gprof(1) call-graph
execution profiler. In typical operation, profiling begins at program startup and ends when the program calls exit. When the program exits,
the profiling data are written to the file gmon.out, then gprof(1) can be used to examine the results.
moncontrol() selectively controls profiling within a program. When the program starts, profiling begins. To stop the collection of his-
togram ticks and call counts use moncontrol(0); to resume the collection of histogram ticks and call counts use moncontrol(1). This feature
allows the cost of particular operations to be measured. Note that an output file will be produced on program exit regardless of the state
of moncontrol().
Programs that are not loaded with -pg may selectively collect profiling statistics by calling monstartup() with the range of addresses to be
profiled. lowpc and highpc specify the address range that is to be sampled; the lowest address sampled is that of lowpc and the highest is
just below highpc. Only functions in that range that have been compiled with the -pg option to cc(1) will appear in the call graph part of
the output; however, all functions in that address range will have their execution time measured. Profiling begins on return from
monstartup().
FILES
gmon.out execution data file
SEE ALSO cc(1), gprof(1), profil(2)4th Berkeley Distribution June 4, 1993 4th Berkeley Distribution
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MONITOR(3) Library Functions Manual MONITOR(3)NAME
monitor, monstartup, moncontrol - prepare execution profile
SYNOPSIS
monitor(lowpc, highpc, buffer, bufsize, nfunc)
int (*lowpc)(), (*highpc)();
short buffer[];
monstartup(lowpc, highpc)
int (*lowpc)(), (*highpc)();
moncontrol(mode)
DESCRIPTION
There are two different forms of monitoring available: An executable program created by:
cc -p . . .
automatically includes calls for the prof(1) monitor and includes an initial call to its start-up routine monstartup with default parame-
ters; monitor need not be called explicitly except to gain fine control over profil buffer allocation. An executable program created by:
cc -pg . . .
automatically includes calls for the gprof(1) monitor.
Monstartup is a high level interface to profil(2). Lowpc and highpc specify the address range that is to be sampled; the lowest address
sampled is that of lowpc and the highest is just below highpc. Monstartup allocates space using sbrk(2) and passes it to monitor (see
below) to record a histogram of periodically sampled values of the program counter, and of counts of calls of certain functions, in the
buffer. Only calls of functions compiled with the profiling option -p of cc(1) are recorded.
To profile the entire program, it is sufficient to use
extern etext();
. . .
monstartup((int) 2, etext);
Etext lies just above all the program text, see end(3).
To stop execution monitoring and write the results on the file mon.out, use
monitor(0);
then prof(1) can be used to examine the results.
Moncontrol is used to selectively control profiling within a program. This works with either prof(1) or gprof(1) type profiling. When the
program starts, profiling begins. To stop the collection of histogram ticks and call counts use moncontrol(0); to resume the collection of
histogram ticks and call counts use moncontrol(1). This allows the cost of particular operations to be measured. Note that an output file
will be produced upon program exit irregardless of the state of moncontrol.
Monitor is a low level interface to profil(2). Lowpc and highpc are the addresses of two functions; buffer is the address of a (user sup-
plied) array of bufsize short integers. At most nfunc call counts can be kept. For the results to be significant, especially where there
are small, heavily used routines, it is suggested that the buffer be no more than a few times smaller than the range of locations sampled.
Monitor divides the buffer into space to record the histogram of program counter samples over the range lowpc to highpc, and space to
record call counts of functions compiled with the -p option to cc(1).
To profile the entire program, it is sufficient to use
extern etext();
. . .
monitor((int) 2, etext, buf, bufsize, nfunc);
FILES
mon.out
SEE ALSO cc(1), prof(1), gprof(1), profil(2), sbrk(2)4th Berkeley Distribution May 15, 1985 MONITOR(3)