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TechKnowSurge Catalog Videos OS Functions: Memory Management
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OS Functions: Memory Management

RAM serves as the staging area between a computer's input and output, and the operating system is responsible for managing how that memory is allocated and used. This content covers how memory addressing works and how to inspect real-time memory allocation using Device Manager and Sysinternals RAMMap.

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About this video

RAM is the bridge between a computer's inputs and its central processing unit. When data enters the system — whether from user input or storage — it is loaded into RAM first, processed by the CPU, and then returned to RAM before being sent to an output destination such as the screen or a storage device. This makes memory management one of the operating system's most critical responsibilities, beginning at the moment the system powers on. During startup, the BIOS is loaded into RAM to handle initial hardware initialization. Once that process completes, the operating system itself is loaded into memory and assumes control over how RAM is allocated and used. Memory is organized into discrete blocks, each identified by a unique physical address, allowing the OS to track exactly which files, drivers, and processes are assigned to which locations at any given time. Two tools illustrate this in practice. Windows Device Manager exposes the memory address ranges assigned to hardware components such as graphics cards, showing how physical devices consume portions of available RAM. Sysinternals RAMMap goes further, providing a detailed breakdown of physical memory pages — categorizing allocations by type, such as active, driver-locked, or file-backed — and mapping individual files to their specific memory addresses. Even on a system with 8 GB of RAM, the volume of physical address entries is substantial, underscoring just how actively the operating system manages memory resources across all running processes and hardware.

What you'll learn

What's covered

OS Memory Management

Aligned to

CompTIA Tech+
3.1 Explain the purpose of operating systems.
2.3 Explain the purpose of common internal computing components.
3.2 Compare and contrast components of an operating system.
CompTIA A+ Core 2
1.3 Given a scenario, use features and tools of the Microsoft Windows 10/11 operating system (OS).
CompTIA A+ Core 1
5.2 Given a scenario, troubleshoot problems related to motherboards, RAM, CPU, and power.
Cisco CCST IT
2.2 Assist end users in using tools to locate information about their device

Key terms

Random Access Memory
RAM
Volatile memory that temporarily stores data and program instructions the CPU is actively using, allowing fast read and write access from any memory location. RAM contents are lost when power is removed, unlike persistent storage.
Operating System
OS
System software that manages hardware resources, provides common services for application software, and acts as an intermediary between users and computer hardware. Examples include Windows, macOS, and Linux.
Central Processing Unit
CPU
The primary processor chip in a computer that executes instructions from programs by performing arithmetic, logic, control, and input/output operations. CPU speed and core count directly affect system performance.
Basic Input/Output System
BIOS
Firmware stored on a motherboard chip that initializes hardware during startup and provides runtime services for the operating system via the Power-On Self-Test (POST) process. BIOS has largely been replaced by UEFI on modern systems.
Memory Address
A unique identifier assigned to each block of RAM that allows the operating system to locate and reference stored data.
Windows Device Manager
A Windows utility that displays hardware devices and their assigned system resources, including memory address ranges.
Sysinternals RAMMap
A Microsoft Sysinternals tool that provides a detailed breakdown of how physical memory is allocated across processes and files.

Topics

Operating Systems Memory Management Ram Memory Addressing Windows Device Manager Sysinternals Rammap

Transcript

One of the jobs of the operating system is to manage the memory on a computer. That is the RAM on the computer. Some of the RAM is allocated during startup to the BIOS, so that way it can do some initial startup and get things going, but then a large portion of it is managed by the operating system.

Memory As A Staging Area

Memory on your computer plays a key role, and that is the RAM. The RAM on your computer is a staging area before things get processed on the central processing unit, or the CPU. What happens is that if there is any kind of input into the system, or things coming from storage, it all goes into RAM initially and then it gets sent off to the CPU to be processed. The answer comes back, or whatever the solution is, whatever gets processed comes back and gets put on RAM before it goes to some sort of output, or storage, or the screen, or wherever it is going off to.

During the startup phase of your computer, initially there is the BIOS that gets loaded into the RAM for initial setup and startup of your computer. Then from there your operating system gets loaded onto the RAM, and then your operating system plays a key role in managing that RAM, or that memory.

Blocks And Addresses

Here is another different view of what that memory, that RAM, looks like. Really what we have here is these blocks of data on that memory, and what we will do is take that input and put those little ones and zeros into one of those blocks before it goes off to be processed. Now, we have to somehow be able to reference these different blocks, so each one of these blocks has an address, and we use that address so we could reference that particular block.

Memory Ranges In Device Manager

I am on my demo laptop here and I wanted to show you a couple of things. The first thing I am going to do is click the start button and type in device manager, and we are going to open up device manager. I am going to go to one of these devices. I am going to take a look at the display adapters, and so this is my graphics card. I am going to open that up and take a look at resources, and I can see the memory ranges that have been assigned to this. So it is using up those resources. I can see that here in the device manager.

Mapping RAM With RAMMap

But there is also another thing that I want to show you, and that is in Sysinternals. I can open up Sysinternals here and I am going to scroll down to RAMMap in here. So there is RAMMap64. I am going to open that up, and it is going to then map out the RAM that we have. It is going to show me some stats here about which processes, or which kind of things, this memory is assigned to. So there is some interesting data here.

But really what I want to do is show you a couple of tabs here. The first tab that I am going to show you is this physical pages here. So this right here is the physical address within the memory, and we can see that this first one is non-paged, whatever that means. We have got active, we have got driver locked. I am going to scroll it down to where we get to a file. Here is a file that is assigned to this block of memory right here. Here is another file that is assigned to this block of memory. So what we are seeing is that these different files and different resources are assigned to these blocks of memory here, and to this physical address of the memory. So that is interesting there.

The other thing that I want to show you is this file details. Within the file details I can see what files are associated to which blocks. So let us take a look at a simple one first. Here is a 4K file right there. I am going to open it up and we can see which physical address within memory it is assigned to.

Let us look at a bigger one now. We have a 13,000 one here, so I open that up and you can see all of the blocks of data that it is assigned to.

And one other thing too is look how much memory we actually have. This is just one file, and look how many memory addresses it is assigned to. If you look at the full thing, we can go back to this physical page and look at how much I scroll through. This is just an 8 GB system, so somewhat small compared to some systems that we have out there, and we have a lot of these physical addresses that are assigned to the RAM that is within here.

So your operating system plays a big role in managing the RAM, or the memory, on your system.

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