virtual memory exhausted: Cannot allocate memory with 8 gb ram

Question

I have code which is 32 bit and i think compiler too. But when i am compiling my c++ code, its taking more than 2 GB memory. As per my understanding on 32 bit system no process can take more than 2 GB.
Any suggestions how can i achieve this? I found lot of posts on this but those
are not helpful as they are adding swaps. But i already have 8 GB ram. So my problem is not available memory, its size of compiling process which could not be more than 2 GB.

Even i have 8 GB ram I have tried to adding swap and that's also not working.

Answer 1

On Windows 32 Bit, the maximum amount of RAM is 4 GB. By default, this address space is seperated into kernel memory and process memory, both being 2 GB large. Most programs don't need more than 2 GB of memory, but if you do, you can enlarge the process memory by specifying the /3GB switch, leaving less memory for the kernel.

Read here for more information: https://msdn.microsoft.com/en-us/library/windows/hardware/ff556232(v=vs.85).aspx

Edit: Keep in mind that if you want to make use of this additional memory, you also need to compile your program with the /LARGEADDRESSAWARE switch. That will set a flag in the Process Environment Block of your program, making Windows aware that your program might need more than 2 GB of memory.

Answer 2

Since you stated you have 8GB of RAM, I am presuming your OS and CPU are actually 64-bit. So you are asking how to make a 32-bit program access more than 2GB of virtual address space, on a 64-bit OS, ie running under WOW64.

In that case, using the /LARGEADDRESSAWARE linker option in Visual Studio will give your app 4GB of virtual address space, under WOW64 . You won't see any benefit in 32-bit Windows, unless you force your users to boot their OS with a certain flag.

I believe your app doesn't really need more than 2GB of RAM, but it's impossible to tell without knowing any details.

In any case, the one correct answer is: switch to a 64-bit app, which will get you 8TB of virtual address space. That's 8 terabytes .