APEX Quickstart¶
Installation¶
For detailed instructions and information on dependencies, see build instructions.
APEX is integrated into the HPX runtime, and is integrated into the HPX build system. To enable APEX measurement with HPX, enable the following CMake flags:
-DHPX_WITH_APEX=TRUE
The CMake flag -DHPX_WITH_APEX_TAG=develop can be used to indicate a specific release version of APEX, or to use a specific GitHub branch of APEX. We recommend using the default configured version that comes with your version of HPX or the develop branch to access the latest features and bug fixes.
Runtime¶
To see APEX data after an HPX run, set the APEX_SCREEN_OUTPUT=1 environment variable. After execution, you'll see output like this:
[khuck@eagle build]$ export APEX_SCREEN_OUTPUT=1
[khuck@eagle build]$ ./bin/fibonacci
fibonacci(10) == 55
elapsed time: 0.112029 [s]
Elapsed time: 0.19137 seconds
Cores detected: 128
Worker Threads observed: 32
Available CPU time: 6.12383 seconds
Timer : #calls | mean | total | % total
------------------------------------------------------------------------------------------------
APEX MAIN : 1 0.191 0.191 100.000
async : 2 0.000 0.000 0.001
async_launch_policy_dispatch : 5 0.001 0.003 0.041
broadcast_call_shutdown_functions_action : 2 0.000 0.001 0.012
call_shutdown_functions_action : 2 0.002 0.005 0.081
fibonacci_action : 174 0.015 2.569 41.957
load_components_action : 1 0.014 0.014 0.230
primary_namespace_colocate_action : 2 0.000 0.001 0.011
run_helper : 1 0.015 0.015 0.250
shutdown_all_action : 1 0.002 0.002 0.040
APEX Idle : 3.514 57.375
------------------------------------------------------------------------------------------------
Total timers : 190
HPX applications can also use the apex_exec wrapper script, please see apex_exec flags for details.