3 #include "gpu_timers.h"
7 pair<GLuint, GLuint> GPUTimers::begin_timer(const string &name, int level)
10 return make_pair(0, 0);
14 glGenQueries(2, queries);
15 glQueryCounter(queries[0], GL_TIMESTAMP);
20 timer.query.first = queries[0];
21 timer.query.second = queries[1];
22 timers.push_back(timer);
26 GLint64 find_elapsed(pair<GLuint, GLuint> queries)
28 // NOTE: This makes the CPU wait for the GPU.
29 GLuint64 time_start, time_end;
30 glGetQueryObjectui64v(queries.first, GL_QUERY_RESULT, &time_start);
31 glGetQueryObjectui64v(queries.second, GL_QUERY_RESULT, &time_end);
32 return time_end - time_start;
35 void GPUTimers::print()
37 for (size_t i = 0; i < timers.size(); ++i) {
38 if (timers[i].level >= 4 && !detailed_timing) {
39 // In practice, only affects the SOR sub-timers.
43 GLint64 time_elapsed = find_elapsed(timers[i].query);
44 for (int j = 0; j < timers[i].level * 2; ++j) {
48 if (detailed_timing) {
49 // Look for any immediate subtimers, and see if they sum to the large one.
50 size_t num_subtimers = 0;
51 GLint64 sum_subtimers = 0;
52 for (size_t j = i + 1; j < timers.size() && timers[j].level > timers[i].level; ++j) {
53 if (timers[j].level != timers[i].level + 1) continue;
55 sum_subtimers += find_elapsed(timers[j].query);
58 if (num_subtimers > 0 && (time_elapsed - sum_subtimers) / 1e6 >= 0.01) {
59 fprintf(stderr, "%-30s %4.3f ms [%4.3f ms unaccounted for]\n", timers[i].name.c_str(), time_elapsed / 1e6, (time_elapsed - sum_subtimers) / 1e6);
61 fprintf(stderr, "%-30s %4.3f ms\n", timers[i].name.c_str(), time_elapsed / 1e6);
64 fprintf(stderr, "%-30s %4.1f ms\n", timers[i].name.c_str(), time_elapsed / 1e6);