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25 .TH SPROF 1 2014-06-24 "Linux" "Linux User Manual"
27 sprof \- read and display shared object profiling data
30 .BR sprof " [\fIoption\fP]... \fIshared-object-path\fP \
31 [\fIprofile-data-path\fP]"
36 command displays a profiling summary for the
37 shared object specified as its first command-line argument.
38 The profiling summary is created using previously generated
39 profiling data in the (optional) second command-line argument.
40 If the profiling data pathname is omitted, then
42 will attempt to deduce it using the soname of the shared object,
43 looking for a file with the name
45 in the current directory.
47 The following command-line options specify the profile output
50 .BR \-c ", " \-\-call\-pairs
51 Print a list of pairs of call paths for the interfaces exported
53 along with the number of times each path is used.
55 .BR \-p ", " \-\-flat\-profile
56 Generate a flat profile of all of the functions in the monitored object,
57 with counts and ticks.
59 .BR \-q ", " \-\-graph
60 Generate a call graph.
62 If none of the above options is specified,
63 then the default behavior is to display a flat profile and a call graph.
65 The following additional command-line options are available:
68 Display a summary of command-line options and arguments and exit.
71 Display a short usage message and exit.
73 .BR \-V ", " \-\-version
74 Display the program version and exit.
78 command is a GNU extension, not present in POSIX.1.
80 The following example demonstrates the use of
82 The example consists of a main program that calls two functions
84 First, the code of the main program:
95 main(int argc, char *argv[])
108 are defined in the following source file that is used to
109 construct the shared library:
113 $ \fBcat libdemo.c\fP
121 for (j = 0; j < lim; j++)
129 for (j = 0; j < 100; j++)
138 for (j = 0; j < lim; j++)
147 for (j = 0; j < 1000; j++)
153 Now we construct the shared library with the real name
154 .IR libdemo.so.1.0.1 ,
160 $ \fBcc \-g \-fPIC \-shared \-Wl,\-soname,libdemo.so.1 \e\fP
161 \fB\-o libdemo.so.1.0.1 libdemo.c\fP
165 Then we construct symbolic links for the library soname and
166 the library linker name:
170 $ \fBln \-sf libdemo.so.1.0.1 libdemo.so.1\fP
171 $ \fBln \-sf libdemo.so.1 libdemo.so\fP
175 Next, we compile the main program, linking it against the shared library,
176 and then list the dynamic dependencies of the program:
180 $ \fBcc \-g \-o prog prog.c \-L. \-ldemo\fP
182 linux\-vdso.so.1 => (0x00007fff86d66000)
183 libdemo.so.1 => not found
184 libc.so.6 => /lib64/libc.so.6 (0x00007fd4dc138000)
185 /lib64/ld\-linux\-x86\-64.so.2 (0x00007fd4dc51f000)
189 In order to get profiling information for the shared library,
190 we define the environment variable
192 with the soname of the library:
196 $ \fBexport LD_PROFILE=libdemo.so.1\fP
200 We then define the environment variable
201 .BR LD_PROFILE_OUTPUT
202 with the pathname of the directory where profile output should be written,
203 and create that directory if it does not exist already:
207 $ \fBexport LD_PROFILE_OUTPUT=$(pwd)/prof_data\fP
208 $ \fBmkdir \-p $LD_PROFILE_OUTPUT\fP
213 causes profiling output to be
215 to the output file if it already exists,
216 so we ensure that there is no preexisting profiling data:
220 $ \fBrm \-f $LD_PROFILE_OUTPUT/$LD_PROFILE.profile\fP
224 We then run the program to produce the profiling output,
225 which is written to a file in the directory specified in
226 .BR LD_PROFILE_OUTPUT :
230 $ \fBLD_LIBRARY_PATH=. ./prog\fP
238 option to generate a flat profile with counts and ticks:
242 $ \fBsprof \-p libdemo.so.1 $LD_PROFILE_OUTPUT/libdemo.so.1.profile\fP
245 Each sample counts as 0.01 seconds.
246 % cumulative self self total
247 time seconds seconds calls us/call us/call name
248 60.00 0.06 0.06 100 600.00 consumeCpu1
249 40.00 0.10 0.04 1000 40.00 consumeCpu2
250 0.00 0.10 0.00 1 0.00 x1
251 0.00 0.10 0.00 1 0.00 x2
257 option generates a call graph:
261 $ \fBsprof \-q libdemo.so.1 $LD_PROFILE_OUTPUT/libdemo.so.1.profile\fP
263 index % time self children called name
265 0.00 0.00 100/100 x1 [1]
266 [0] 100.0 0.00 0.00 100 consumeCpu1 [0]
267 \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
268 0.00 0.00 1/1 <UNKNOWN>
269 [1] 0.0 0.00 0.00 1 x1 [1]
270 0.00 0.00 100/100 consumeCpu1 [0]
271 \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
272 0.00 0.00 1000/1000 x2 [3]
273 [2] 0.0 0.00 0.00 1000 consumeCpu2 [2]
274 \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
275 0.00 0.00 1/1 <UNKNOWN>
276 [3] 0.0 0.00 0.00 1 x2 [3]
277 0.00 0.00 1000/1000 consumeCpu2 [2]
278 \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
282 Above and below, the "<UNKNOWN>" strings represent identifiers that
283 are outside of the profiled object (in this example, these are instances of
288 option generates a list of call pairs and the number of their occurrences:
292 $ \fBsprof \-c libdemo.so.1 $LD_PROFILE_OUTPUT/libdemo.so.1.profile\fP
304 This page is part of release 3.79 of the Linux
307 A description of the project,
308 information about reporting bugs,
309 and the latest version of this page,
311 \%http://www.kernel.org/doc/man\-pages/.