Even though this post says it should work, if you create an int array of size Int32.MaxValue, it throws an OutOfMemoryException: Array dimensions exceeded supported range.
From my testing, it seems like the maximum size that an array can be initialized to is Int32.MaxValue - 1048576 (2,146,435,071). 1048576 is 2^20. So only this works:
var maxSizeOfIntArray = Int32.MaxValue - 1048576;
var array = new int[maxSizeOfIntArray];
Does any one know why? Is there a way to create a larger integer array?
PS: I need to use arrays instead of lists because of a Math.Net library that only returns arrays for sets of random numbers that are cryptographically secure pseudo random number generator
Yes I have looked at the other questions linked but they are not correct as those questions say the largest size is Int32.MaxValue which is not the same as what my computer lets me do
Yes, I do know the size of the array will be 8GB, I need to generate a data set of billions of rows in order to test the randomness with the die harder suite of tests
I also tried the option of creating a BigArray<T> but that doesn't seem to be supported in C# anymore. I found one implementation of it, but that throws an IndexOutOfRangeException at index 524287, even though I set the array size to 3 million.
An
Int32is 32 bits, or 4 bytes. The max value of anInt32is 2,147,483,647. So, if you could create an array of 2,147,483,647 elements, where each element is 4 bytes, you would need a contiguous piece of memory that is 8GB in size. That is ridiculously huge, and even if your machine had 128GB of RAM (and you were running in a 64-bit process), that would be outside of realistic proportions. If you really need to use that much memory (and your system has it), I would recommend going to native code (i.e., C++).