2 replies to this topic

[the dodger uk]

ok , i have a weird problem , i just ran a long test

 

if i run my project in visual studio debug , it takes 11min 23 seconds to load and run

 

if i copy over the debug.exe and run it from project folder , it takes 27 seconds

 

 

i  have to assume i  did something odd in the settings in visual studio, any one any ideas

[SiCrane]

When run from the debugger an MSVC application will have a few differences. For example, IsDebuggerPresent() will return true rather than false. The biggest difference from a performance standpoint is that the debug memory allocator will be used. Allocations will be larger with more sanity checking information, impacting cache misses and increasing the time necessary for each allocation and deallocation. If your program does a lot of small allocations this can really add up.

[Nik02]

Furthermore, Visual Studio tries to find all the symbols for all runtime dependencies of your program, sets up thread monitoring, builds runtime metadata for your variables, etc.