Clocks Test

Set of tools which allow to test how STL and Boost performs on your platform in case of system time changed. Currently contains tests for chrono::steady_clock, chrono::system_clock, sleep methods of this_thread and wait methods of condition_variable and future.

And yes, this project is released to public domain.

Prerequisities

• MS Visual Studio 2012 or any other compiler supporting C++11. Clang in conjunction with libc++ (both included in Xcode now) is the best choice btw ;)
• CMake version 2.8.10 or newer.
• Boost version 1.54 or above. The following Boost libraries are need to be compiled: system, chrono, thread.

Most probably the earlier versions of CMake and Boost are also OK. Note that before using them you have to change version requirements in CMakeLists.txt file.

##How To Build

*nix / OS X:

mkdir workspace
cd workspace
cmake <path_to_clocks_test>
make

Windows (Visual Studio 2012):

mkdir workspace
cd workspace
cmake <path_to_clocks_test> -G "Visual Studio 11" -DBOOST_INCLUDEDIR=<path_to_boost_headers> -DBOOST_LIBRARYDIR=<path_to_boost_libs>

Then either build it by

cmake --build . --config Release

or open generated solution file.

Please read CMake documentation to get more options and take complete control over build.

Tests included

clocks_test

Tests chrono::system_clock and chrono::steady_clock.

To test:

• Run ./clocks_test.
• When prompted, change system time for one minute back or forward or back then forward or whatever case you want to test.
• Press Enter to finish test execution.

Output format:

                                    t0, ticks           t1, ticks          t1 - t0, s
std          system_clock    1379539687034393    1379539658598580            -28.4358
std          steady_clock      11785328391541      11819486797225             34.1584
boost        system_clock 1379539687034400000 1379539658598582000            -28.4358
boost        steady_clock      11785328412464      11819486798474             34.1584

Where t0 is the clock's value at program start and t1 the one at the program finish.

sleep_test

Tests this_thread methods:

• sleep_for(duration)
• sleep_until(steady_clock::time_point)
• sleep_until(system_clock::time_point)

To test:

• Prepare to be ready to change system clock in several seconds (open corresponding page of System Preferences or similar).
• Run ./sleep_test.
• Change system time for one minute back or forward or back then forward or whatever case you want to test. But do it quickly!
• Wait until test execution finished.

Output format:

std         sleep_until_steady  timings, s:    15.0011 (std)   15.0011 (boost)
std                  sleep_for  timings, s:    15.0011 (std)   15.0011 (boost)
boost       sleep_until_steady  timings, s:    15.0012 (std)   15.0012 (boost)
boost                sleep_for  timings, s:    15.0012 (std)   15.0012 (boost)
std         sleep_until_system  timings, s:    77.1577 (std)   77.1577 (boost)
boost       sleep_until_system  timings, s:    77.1578 (std)   77.1578 (boost)

Where timings are taken from STL and Boost steady_clock.

wait_test

Tests condition_variable and future methods:

• wait_for(duration)
• wait_until(steady_clock::time_point)
• wait_until(system_clock::time_point)

To test:

• Prepare to be ready to change system clock in several seconds (open corresponding page of System Preferences or similar).
• Run ./wait_test.
• Change system time for one minute back or forward or back then forward or whatever case you want to test. But do it quickly!
• Wait until test execution finished.

Output format:

std future        wait_until_steady  timings, s:    15.0005 (std)   15.0005 (boost)     timeout
std cv                     wait_for  timings, s:    15.0005 (std)   15.0006 (boost)     timeout
boost cv                   wait_for  timings, s:    15.0006 (std)   15.0007 (boost)     timeout
std cv            wait_until_steady  timings, s:    15.0006 (std)   15.0007 (boost)     timeout
std future                 wait_for  timings, s:    15.0005 (std)   15.0006 (boost)     timeout
boost future               wait_for  timings, s:    15.0006 (std)   15.0006 (boost)     timeout
std cv            wait_until_system  timings, s:    15.0007 (std)   15.0009 (boost)  no_timeout
boost cv          wait_until_system  timings, s:    15.0007 (std)   15.0009 (boost)     timeout
boost future      wait_until_steady  timings, s:    15.0008 (std)   15.0008 (boost)     timeout
boost future      wait_until_system  timings, s:    15.0008 (std)   15.0008 (boost)     timeout
boost cv          wait_until_steady  timings, s:    15.0008 (std)   15.0009 (boost)     timeout
std future        wait_until_system  timings, s:    77.3298 (std)   77.3298 (boost)     timeout

Where timings are taken from STL and Boost steady_clock. Last column is a result of wait. It either cv_status or future_status type.