1 /*
2 ** Copyright 2008 The Android Open Source Project
3 **
4 ** Licensed under the Apache License, Version 2.0 (the "License");
5 ** you may not use this file except in compliance with the License.
6 ** You may obtain a copy of the License at
7 **
8 **     http://www.apache.org/licenses/LICENSE-2.0
9 **
10 ** Unless required by applicable law or agreed to in writing, software
11 ** distributed under the License is distributed on an "AS IS" BASIS,
12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 ** See the License for the specific language governing permissions and
14 ** limitations under the License.
15 */
16 
17 #include <stdlib.h>
18 #include <stdio.h>
19 #include <errno.h>
20 #include <sys/time.h>
21 #include <sys/uio.h>
22 #include <unistd.h>
23 
24 int main(int argc, char **argv) {
25     int i;
26 
27     struct timeval tv1;
28     struct timeval tv2;
29     long max = 0;
30     long avg = 0;
31 
32     for(i = 1; ; i++) {
33         gettimeofday(&tv1, NULL);
34         usleep(1000);
35         gettimeofday(&tv2, NULL);
36 
37         long usec = (tv2.tv_sec - tv1.tv_sec) * 1000000 + tv2.tv_usec - tv1.tv_usec;
38         avg += usec;
39 
40         if (usec > max) max = usec;
41         if (!(i % 1000)) {
42             avg /= 1000;
43             printf("max %ld\tavg %ld\n", max, avg);
44             max = 0;
45             avg = 0;
46         }
47     }
48     return 0;
49 }
50