Is there any way to determine the available Stack Space at Run Time?

What is stack space?

A stack is an area of memory used to temporarily store information in a computer program. It is a common data structure that consists of a series of layers, called frames or levels. Each layer can be one or more cells. The size and number of the various layers are typically then dictated by the computer architecture and architecture-specific parameters.

In computer science, stack space is the amount of memory allocated for storing stack frames.

Stack space is used by the CPU to store instructions and data which are in execution order. If an interrupt occurs when instructions are stored on the stack, some instructions might be moved from the top of the stack to a saved location, similar to temporary memory. The saved location contains a specific number indicating how many bytes are available for this data on that physical address range.
The maximum amount of available stack space depends on any combination of data type and machine architecture in use. In 64-bit architectures, for example, the maximum available stack space can be up to 16 exabytes.

The stack grows from the bottom, adding new instructions and data to the top in execution order. If space becomes available during execution, then some instructions can be copied to a memory location called the “spare area, ” and saved for later execution. Most modern operating systems (e.g., Windows Vista/7) provide mechanisms that prevent this type of issue by using a feature called “Stack Paging.”

How is the stack different from the heap?

The stack is the place where a program allocates storage for variables, temporaries, functions, and other objects. The heap is where these objects are actually stored. 

• In some programming languages, global variables are physically stored on the heap. But in most languages including most high-level ones like C & C++ keeping track of the physical address of an object also means keeping track of its lifetime so it can be deleted at a later time.
• In C++ everything is allocated in the heap and deleted from there. In other programming languages such as Java & C# there is no difference between the two or they share the same space.

What is Runtime stack space?

Runtime stack space is the amount of address space allocated to the program when it executes. It is usually measured in kilobytes on x86 and in megabytes on x64 machines. On 64-bit platforms, it may be a multiple of the amount of physical memory.

Just-in-time (JIT) stack is a type of immediate mode execution that uses static variables, which are laid out in memory contiguous with our program data, as a runtime stack. The language runtime takes care of all routine bookkeeping such as function activation and switching between routines within a single executable thread.

How to calculate available Stack Space at run time?

Many code lines have a secret automatically calculated by the developer of the program. If you want to know how much free stack you have for your new computer program, just follow these few steps and watch your calculations appear before your eyes.

1. In the Windows Resource Monitor add a new counter: “Available memory”.
2. Start the program that needs to calculate how many stacks you have. This can be another program or a background service or task on your computer.
3. Set the Data Type to “Stack Usage” and the “Start Time” field to now (if this is not the current time then just change it to now or any future time, but not a past time). You might want to set the Maximum Number of Items in Stack Row and Maximum Number of Items in Time-Series Row both equal 1 so that only one item appears in each row. This will make your calculations much easier.
4. Press the “Add” button and then select “Apply”. By doing this any data received on your computer will be monitored and sent to the Windows Resource Monitor.
5. In the Windows Resource Monitor, you will see counters added after step #3. Click on “Available memory” in the Windows Resource Monitor and see how much free stack space is available for use by your program!

Note: This is not a perfect way to determine how much free stack you have available to you because it does not take into account any other programs that might be using stack space as well as yours, but it gives you a good indication of how much usable stack space you have available.

Important points: 

• With a stack, the number of frames at any given time is finite and bounded by the architecture. In other words, there is a maximum stack depth that can be reached by a program. This has led to questions such as:
• Stack space analysis is an area of active research in many sub-areas of computer science that focus on detecting possible causes for exceeding the maximum stack depth. The analysis of these parameters can be used to provide guidelines and discoveries on how a program may be optimized or improved.
• Stack space is one of the possibilities in the hierarchy of resource consumption that is used in computer programming. Other forms are the amount of memory (RAM) needed by all registers, the amount of working memory required, and the amount of storage needed for being able to contain stack data. Each type of resource depletes itself at different rates, so it is important to know what each one accounts for when trying to maximize available resources.
• CPU time is a measure of the time the CPU requires to execute instructions. Generally, it is assumed that CPU time increased linearly with program size and that it remains constant, or at least very small, through all execution cycles. However, this assumption can be broken when dealing with large programs that continuously spend a lot of random cycles on a loop. The use of dynamic analysis can help to identify these routines in order to do further optimizations.
• Code reuse helps to reduce the cost of development and maintenance by allowing easier changes in various components. In high-level languages such as C++, C#, and Java this means that they are more able to hand off code sections where needed instead of rewriting them from scratch each time the need arises.

Conclusion:

The use of dynamic analysis tools for resource consumption can help to answer some of these questions by looking at the various elements of interest at runtime. These tools can then be used to gather data about the stack, and thus provide some reasonable predictions about behavior.