Slow or delayed loading of my application - c++

Question

Question:
My question is what will be the impact on my application memory footprint or performance if I replace functions like foo1 (which I have in my code) below with foo2. This function is called frequently in application.
#define SIZE 5000
void foo1()
{
double data[SIZE];
// ....
}
void foo2()
{
std::unique_ptr< double[] > data( new double[SIZE] );
// ....
}
Context:
My MFC application loads really slow on the embedded device running Windows 7 after implementation of new features/modules. The same application loads fast on PC. At least one of the difference and what I suspect is the cause is RAM on embedded unit is really low, just 768 MB.
I debugged it to find out where does this delay occurs and recorded time stamps within application in loading process. What I discovered was interesting. When I double click the exe, it takes about a minute to record the first time stamp and after that it runs fast, so all the delay is right there.
My theory is that windows is taking all this time to setup the environment for exe and once done, it runs fast. The reason I suspect this is there are a lot big structures declared on stack in the application to the point I had to move some of them to heap to get rid of stack overflow errors even on PC with new features.
What do you think is the cause of the slow or more accurately delayed loading of executable on low RAM machine? Do you think it will fix up if I move all of the big structures from stack to heap?

Answer 1

There are not a lot of things that take a minute in modern day computing. Not on a machine with an embedded version of Windows either. Not the processor, not the RAM, not the disk.
Except one, networking is still based on assumptions that were last valid in the 1980s. TCP/IP has taken over as the only protocol in common use. But has a flaw, there is no reasonable way to discover how long a connection attempt might take. So connection timeouts are based on absolute worst-case conditions, trying to hook up to a machine half-way around the world, connected with a modem that needs to spin up the drum to load the program.
The minimum timeout on Windows is hard-baked at 45 seconds. And, in general, a condition that certainly isn't unlikely in an embedded machine. You might have hooked it up to a network to get it initialized but it isn't connected anymore or the machine you copied from might no longer be powered up.
Chase it down by first looking for a disconnected disk drive, very common. Next use SysInternals' utilities like TcpView to look for network activity, like trying to connect to a CRL server. Use Process Explorer to find out where the program is stuck. Mark Russinovich' blog is excellent to show his trouble-shooting strategies using these tools. Good luck with it.