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Diffstat (limited to 'ml/dlib/dlib/timing.h')
| -rw-r--r-- | ml/dlib/dlib/timing.h | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/ml/dlib/dlib/timing.h b/ml/dlib/dlib/timing.h new file mode 100644 index 000000000..2d5116ade --- /dev/null +++ b/ml/dlib/dlib/timing.h @@ -0,0 +1,196 @@ +// Copyright (C) 2011 Davis E. King (davis@dlib.net) +// License: Boost Software License See LICENSE.txt for the full license. +#ifndef DLIB_TImING_Hh_ +#define DLIB_TImING_Hh_ + +#include <chrono> +#include <atomic> +#include <cstring> +#include "string.h" + +#include <iostream> + +// ---------------------------------------------------------------------------------------- + +/*!A timing + + This set of functions is useful for determining how much time is spent + executing blocks of code. Consider the following example: + + int main() + { + using namespace dlib::timing; + for (int i = 0; i < 10; ++i) + { + // timing block #1 + start(1,"block #1"); + dlib::sleep(500); + stop(1); + + // timing block #2 + start(2,"block #2"); + dlib::sleep(1000); + stop(2); + } + + print(); + } + + This program would output: + Timing report: + block #1: 5.0 seconds + block #2: 10.0 seconds + + So we spent 5 seconds in block #1 and 10 seconds in block #2 + + + + Additionally, note that you can use an RAII style timing block object. For + example, if we wanted to find out how much time we spent in a loop a convenient + way to do this would be as follows: + + int main() + { + using namespace dlib::timing; + for (int i = 0; i < 10; ++i) + { + block tb(1, "main loop"); + + dlib::sleep(1500); + } + + print(); + } + + This program would output: + Timing report: + block main loop: 15.0 seconds + +!*/ + +// ---------------------------------------------------------------------------------------- + +namespace dlib +{ + namespace timing + { + const int TIME_SLOTS = 500; + const int NAME_LENGTH = 40; + + inline std::atomic<uint64_t>* time_buf() + { + static std::atomic<uint64_t> buf[TIME_SLOTS]; + return buf; + } + + inline char* name_buf(int i, const char* name) + { + static char buf[TIME_SLOTS][NAME_LENGTH] = {{0}}; + // if this name buffer is empty then copy name into it + if (buf[i][0] == '\0') + { + using namespace std; + strncpy(buf[i], name, NAME_LENGTH-1); + buf[i][NAME_LENGTH-1] = '\0'; + } + // return the name buffer + return buf[i]; + } + + inline uint64_t ts() + { + using namespace std::chrono; + return duration_cast<duration<double,std::nano>>(high_resolution_clock::now().time_since_epoch()).count(); + } + + inline void start(int i) + { + time_buf()[i] -= ts(); + } + + inline void start(int i, const char* name) + { + time_buf()[i] -= ts(); + name_buf(i,name); + } + + inline void stop(int i) + { + time_buf()[i] += ts(); + } + + inline void print() + { + using namespace std; + cout << "Timing report: " << endl; + + // figure out how long the longest name is going to be. + unsigned long max_name_length = 0; + for (int i = 0; i < TIME_SLOTS; ++i) + { + string name; + // Check if the name buffer is empty. Use the name it contains if it isn't. + if (name_buf(i,"")[0] != '\0') + name = cast_to_string(i) + ": " + name_buf(i,""); + else + name = cast_to_string(i); + max_name_length = std::max<unsigned long>(max_name_length, name.size()); + } + + for (int i = 0; i < TIME_SLOTS; ++i) + { + if (time_buf()[i] != 0) + { + double time = time_buf()[i]/1000.0/1000.0; + string name; + // Check if the name buffer is empty. Use the name it contains if it isn't. + if (name_buf(i,"")[0] != '\0') + name = cast_to_string(i) + ": " + name_buf(i,""); + else + name = cast_to_string(i); + + // make sure the name is always the same length. Do so by padding with spaces + if (name.size() < max_name_length) + name += string(max_name_length-name.size(),' '); + + if (time < 1000) + cout << " " << name << ": " << time << " milliseconds" << endl; + else if (time < 1000*60) + cout << " " << name << ": " << time/1000.0 << " seconds" << endl; + else if (time < 1000*60*60) + cout << " " << name << ": " << time/1000.0/60.0 << " minutes" << endl; + else + cout << " " << name << ": " << time/1000.0/60.0/60.0 << " hours" << endl; + } + } + } + + inline void clear() + { + for (int i = 0; i < TIME_SLOTS; ++i) + { + // clear timing buffer + time_buf()[i] = 0; + // clear name buffer + name_buf(i,"")[0] = '\0'; + } + } + + struct block + { + /*! + WHAT THIS OBJECT REPRESENTS + This is an RAII tool for calling start() and stop() + !*/ + + block(int i):idx(i) {start(idx);} + block(int i, const char* str):idx(i) {start(idx,str);} + ~block() { stop(idx); } + const int idx; + }; + } +} + + +#endif // DLIB_TImING_Hh_ + |