What is kernel isolation and why does it affect performance in Windows 11?

¿What is kernel isolation and why does it affect performance in Windows 11? If you use Windows 10 or Windows 11, you've probably come across the option at some point to “Kernel Isolation” in Windows Security And you're left with a blank stare: What is this? Does it do anything? Why do some games run worse when you activate it? In this article, you'll find out once and for all.

Let's look at it in detail What is kernel isolation, what role does memory integrity play, and how does it affect performance? (especially in games) and what alternatives you have if your PC isn't compatible or you prefer a different security strategy. You'll also see how to enable or disable it in Windows 10 and Windows 11 and what hardware and BIOS requirements you need to meet.

What is kernel isolation in Windows?

The so-called core isolation, or core isolation in Microsoft terminologyIt is an advanced security feature built into Windows that relies on hardware virtualization to create a sort of bubble around the most sensitive processes of the operating system.

In practice, what it does is that the most critical components of Windows (the kernel and certain high-security processes) They do not run in the same memory space as the rest of the processes and drivers. Instead, they run in a virtualized environment monitored by a hypervisor, which greatly reduces the possibility of malicious code infiltrating the kernel.

Think of it as if Windows were to raise a “virtual wall” between the system core and the rest of the softwareThus, if malware tries to exploit a vulnerability in a driver or application to escalate privileges, it encounters an additional barrier before it can reach the heart of the system.

This feature is especially relevant against attacks that attempt to operate at a very low level, for example malware that disguises itself as a device driver, rootkits or techniques that attempt to inject code into privileged system processes.

Closely related to core isolation is another fundamental pillar: the memory integrity (Memory Integrity or HVCI), which is the part you'll see most often in the Windows Security interface and the one that usually causes headaches with performance and driver compatibility.

What is High-Visual Memory Integrity (HVCI) and how does it work?

Within the core isolation section you will see an option called “Memory integrity”This function, also known as HVCI (Hypervisor-Protected Code Integrity), is responsible for preventing untrusted code from running in high-security processes, especially at the kernel level.

To achieve this, Windows uses hardware virtualization to create an isolated environment that It protects code that runs with elevated privileges.Thus, drivers and components that attempt to load in that sensitive area must meet certain signature and security requirements; otherwise, they are blocked.

Imagine you open a malicious email attachmentWithout these protections, malware could attempt to exploit a vulnerability in a system driver or service to infiltrate the kernel. With memory integrity enabled, the malware code is "locked" in a less privileged environment and cannot be injected where it would cause the most damage.

In addition to memory integrity, Microsoft offers an additional option called “Microsoft’s blocked list of vulnerable drivers”When enabled, Windows prevents certain drivers that Microsoft itself has categorized as problematic or with known vulnerabilities from loading.

This entire approach fits within the virtualization-based security strategy, where The highest risk processes are kept separate from the rest of the system to limit the scope of the attacks. Of course, all this magic doesn't come free: it requires resources and compatible hardware.

Primary vs. peripheral hardware and why it matters in isolation

To understand why this function is so critical, it's helpful to clarify what Windows means by primary hardware and peripheral hardwareThe isolation of the core is closely linked to the interaction between both worlds.

Primary hardware includes all components without which the computer could not start or function: motherboard, processor, graphics card, RAM and main storage unit (HDD or SSD). They are the foundation on which the system runs.

In contrast, anything you plug in externally or that is not essential for starting the engine is considered as peripheral hardwareUSB drives, external hard drives, printers, wired smartphones, webcams, etc. All these devices communicate with the system through drivers.

Core isolation and memory integrity seek, precisely, to build a wall between that primary hardware and the "dirtier" world of peripheralsThe idea is that, even if a USB drive or external device carries malicious software, it cannot compromise the core or the most sensitive components.

This approach is especially useful in scenarios where connections are made devices of dubious origin or sharedsuch as offices, libraries, educational centers, cybercafés or any environment where many people use the same equipment.

Why core insulation affects performance

One of the most common complaints when users enable memory integrity is that They start to notice the computer is "heavier", with lower FPS in games or with small stutters.It's not imagination: this extra layer of protection comes at a real cost in resources.

To understand this, imagine you want to enter your home and, instead of opening the door yourself, you have a A security guard asks for your ID, checks that you're not carrying anything dangerous, and verifies on a list if you're authorized.You'll get in more safely, yes, but it will take you longer to cross the threshold.

Kernel isolation works similarly. Whenever a process or driver wants to do something sensitive, Windows must validate that the code is legitimate, properly signed, and has not been tampered withThis check requires CPU time and, in many cases, also involves additional memory usage.

The more layers of protection you add (memory integrity, blocked driver list, other security features), The system has more work to do to verify everythingIt's a bit like when the antivirus performs a deep scan: the computer continues to function, but it's noticeably more overloaded.

For the average user who only performs office tasks, browsing, and little else, this loss may be acceptable. However, if you use the computer for gaming or for performance-sensitive tasks (video editing, 3D rendering, etc.), FPS drops or micro-stuttering can be annoying.

Many users have reported that, after activating core isolation, Their games lose performance or suffer FPS dropsand that disabling it resolves the problem. There are also cases of blue screens when trying to activate the function due to incompatible drivers. You might find this article helpful. How to enable hidden power plans in Windows 11.

Security advantages versus performance loss

The big question is: is it worth activating core isolation despite the cost? The answer depends on how you use the PC and what level of risk you assume when you browse or install programs.

If you're someone who only downloads software from official sources, avoid suspicious websites, don't open strange attachments, and always keep Windows Defender (or any other antivirus) up to dateYou probably already have a fairly reasonable level of protection without needing to activate all the advanced features.

However, if the computer is used to access many different websites, download files from various sources, test little-known programs, or share USB drives with other people, Having active kernel isolation and memory integrity is highly recommendedIn these environments, the risk of a device or file carrying malware is much higher.

It is worth emphasizing that this function It does not replace antivirus software.Windows Defender continues to scan files, detect suspicious behavior, and block threats in real time. Kernel Isolation is an add-on that provides a final, low-level line of defense.

Ultimately, it's about finding a balance: Maximum safety versus maximum performanceOn powerful PCs, the penalty is less severe and it's usually worth keeping it enabled. On systems with limited resources or those focused on gaming, disabling it can make sense, provided you strengthen your online security practices.

How to enable or disable kernel isolation in Windows 11

In Windows 11, core isolation configuration is quite simple and is managed from the application. Windows Security, the blue shield-shaped panel you see in the notification area next to the clock.

If you can't find the icon, you can use the shortcut Windows + S to open search and type “Windows Security”. Once inside, follow these steps to enable memory integrity:

1. Open the app Windows Security from the Start menu or the system tray.
2. In the side menu, enter the section Device security.
3. Locate the block called Core insulation and press on Core insulation details.
4. You will see the option Memory integrityIf it is off, switch it to on.
5. You may also see the option Microsoft's list of blocked vulnerable driversIt's usually best to leave it on.
6. Windows will ask you to restart the computer to apply the changes.

Upon restarting, if everything has gone well, you will return to Windows Security, in Device security > Core isolation, and you should see a green icon indicating that the protections are enabled correctly.

If at any point you notice performance problems, incompatibility with any device, or even blue screens, you can return to this same menu and disable memory integrityAfter another restart, the changes will take effect.

Please note that the feature can be turned on and off. as many times as you wantFor example, you could activate it when you're going to connect a USB drive of unknown origin or when you download suspicious software, and deactivate it afterwards if you need to get the most out of the performance for gaming.

How to enable kernel isolation in Windows 10

Windows 10 also has kernel isolation, but with some nuances: Not all editions include it. And the way to activate it is somewhat different, especially if you want to use related features like Windows Sandbox.

First, this feature is only officially available in Windows 10 Pro (and higher editions)If you use Windows 10 Home, it's normal that when you search for "Kernel Isolation" you get a message like "Page unavailable" in the security summary, because your edition doesn't support it.

If you have Windows 10 Pro, you can check and enable memory integrity in a very similar way to Windows 11:

1. Press Windows + I to open the Settings app.
2. Enter Updates and security.
3. In the menu on the left, select Windows Security.
4. Click on Open Windows Security.
5. Within Windows Security, go to Device security.
6. Click on Core insulation and then in Details.
7. In the section of Memory integrity, activate the switch if it is disabled.

On many computers with a fresh Windows 11 Pro installation and a properly configured BIOS, this feature is usually enabled by default. In Windows 10, however, It often needs to be activated manually and make sure beforehand that the hardware and BIOS are compatible.

It is important to know that these functions rely on virtualization technologies such as Intel VT-x or AMD SVMIf your processor is not compatible or the option is disabled in the BIOS, you will see that some options related to isolation or Windows Sandbox appear disabled.

In the case of Windows 10 Pro, in addition to memory integrity, you can enable the feature “Windows Sandbox”which allows you to run a temporary and completely isolated Windows environment to test programs and visit websites without risk to the main system.

Hardware requirements, BIOS, and driver compatibility

For kernel isolation and memory integrity to function, the system needs to meet a series of hardware requirements and BIOS/UEFI configurationNot all PCs on the market can take advantage of these features.

First, you need a modern CPU with support for hardware virtualizationVT-x on Intel processors or SVM (sometimes called AMD-V) on AMD processors. These options usually appear in the BIOS/UEFI and, in some cases, are disabled by default.

If you have a Gigabyte motherboard, for example, you will need to Restart your PC, enter BIOS (F2, F12 or Delete depending on the model)Switch to advanced mode and look in the CPU options for something like “SVM Mode” or “Intel Virtualization Technology”. If they are set to “Disabled”, set them to “Enabled”, save the changes, and exit.

Once virtualization is enabled, Windows can use these capabilities to set up the isolated environment where critical processes runWithout that foundation, the memory integrity or sandbox options will appear grayed out or unavailable.

Another key point is driver compatibility. Memory integrity requires that drivers meet certain security requirements, and Not all old or poorly designed drivers pass the filterWhen Windows detects an incompatible driver, it may prevent you from activating the feature or display a warning.

In those cases, it is advisable to visit the website of device manufacturer or application developer and look for an updated version of the driver that is already compatible. If there isn't a new driver and you absolutely need that function, you may have to uninstall the device or the program that uses that driver.

Hardware-enforced stack protection (Shadow Stack and CET)

In addition to the isolation of the classic kernel, Windows integrates another layer of defense called hardware forced stack protectionwhich is also managed from the advanced Windows Security options and requires modern CPUs with specific functions.

This protection is designed to hinder attacks that They modify the return addresses on the kernel-mode stackThis is a classic technique for redirecting code execution to malicious areas. To do this, the CPU maintains a parallel copy (shadow stack) with the valid return addresses.

When the kernel executes code, the CPU stores return addresses both on the normal stack and on that stack. read-only pile of shadowsIf a malicious program or driver attempts to manipulate the return address on the conventional stack, the CPU detects the discrepancy by comparing it to the copy on the shadow stack.

If something is detected as amiss, the processor forces a serious error (typical blue screen) to prevent the malicious code from executing. It's a drastic but very effective reaction to nip these types of attacks in the bud.

This function requires a CPU that implements technologies such as Intel Control-Flow Enforcement Technology (CET) or AMD Shadow StackIn addition to having memory integrity enabled, driver compatibility also comes into play: some legitimate drivers modify return addresses for non-malicious reasons and are not compatible with this protection.

If, when trying to activate the hardware-enforced battery protection, you receive a warning indicating that There is an incompatible driver or service.You'll need to check which device or app is using it and see if the manufacturer offers a compatible version. Sometimes an update will suffice; other times, you may have to uninstall the software to activate the protection.

Windows Sandbox and .wsb files: an extra isolated environment

While not exactly the same as kernel isolation, the Windows 10 and 11 ecosystem includes another tool that leverages virtualization to improve security: Windows Sandbox or Windows Isolated Space, available in Pro editions.

Windows Sandbox is a virtual machine with a clean Windows installation It's created every time you start it and is destroyed when you close it. It has network access but is isolated from the host system. You can copy programs and documents into it, run them, and when you close the sandbox window, everything you've done there disappears without a trace.

This makes it a perfect tool for testing software from dubious sources or visiting potentially dangerous websites without putting the main system at risk. However, it's advisable to disable the network within the sandbox if you're going to run something truly suspicious, to prevent it from trying to spread across the local network.

To use Windows Sandbox in Windows 10 Pro, you must go to the Control Panel, then enter Programs and Features > Turn Windows features on or off and check the "Windows Sandbox" box. After restarting, the application will be available.

Furthermore, Sandbox allows a high degree of Automation and configuration using .wsb files in XML formatIn these files you can define things like which host system folders will be mapped within the sandbox, whether you want to disable the network, adjust the amount of RAM allocated, or run commands at startup.

For example, you could create a .wsb file that maps a folder on the host to the sandbox desktop, and upon startup, Run mstsc.exe with an .rdp file It's pre-designed to connect to a Remote Desktop server from that isolated environment. This way, your credentials are never stored on your main machine.

Another typical use is to prepare a .cmd script that, when the sandbox starts, silently install a specific application (for example, 7-Zip) by first copying the installer to the mapped folder and launching it with /S parameters. Everything remains within the sandbox and will be lost when you close it.

This ability to create disposable and automated environments adds an extra layer of security and flexibility, especially in professional settings where it is desired limit the impact of potential incidents and prevent sensitive credentials or data from being exposed on the host computer.

Ultimately, kernel isolation, memory integrity, hardware stack protection, and tools like Windows Sandbox form a set of defenses that, when properly configured, They greatly strengthen Windows security against advanced attacksThe price to pay is a certain loss of performance and the need for modern hardware and up-to-date drivers, so each user must assess what is most worthwhile for them based on their equipment and how they use it.