[DOCS] Documenting RT jitter on PTL platforms with kernel Next (#786)

* [DOCS] Documenting RT jitter on PTL platforms with kernel Next

Signed-off-by: Sebastian Golebiewski <sebastianx.golebiewski@intel.com>

* Update platform details

Signed-off-by: Sebastian Golebiewski <sebastianx.golebiewski@intel.com>

---------

Signed-off-by: Sebastian Golebiewski <sebastianx.golebiewski@intel.com>

Author: sgolebiewski-intel

docs/developer-guide/emt-architecture-overview.md

@@ -32,7 +32,7 @@ The toolkit comes pre-configured to produce different images; the following tabl
 | Capabilities | <ul><li>Easy to install, bootable ISO image with precompiled packages for developer evaluation.</li> <li> Includes installable rpms with TDNF for extending baseline functionality.</li> <li>Complete with a toolkit to build an image with opt-in data integrity and security features.</li></ul> | <ul><li>Designed for [Edge Manageability Framework](https://github.com/open-edge-platform/edge-manageability-framework) and can be used to onboard and provision edge nodes at scale.</li><li>Can be used independently on bare metal or as a guest OS.</li><li>Fast atomic updates and rollback support with a small image footprint and short boot time.|
 | Image Type       | Mutable ISO          | Immutable RAW + VHD                               |
 | Update Mechanism | RPM package updates with TDNF | Image based A/B updates + Rollback       |
-| Linux Kernel     | Intel® Kernel 6.12   | Intel® Kernel 6.12                                |
+| Linux Kernel     | Intel® “Next” Kernel 6.17   | Intel® “Next” Kernel 6.17                                |
 | Real time        | Available for opt-in | Image variants with standard and RT kernel provided |
 | Desktop Virtualization | Available      | Dedicated non-RT image variant provided                                    |
 | Add-on packages  | Available for opt-in: Docker + K3s | Downloaded during installation: K3s and extensions    |
@@ -115,7 +115,7 @@ The RT version of Edge Microvisor Toolkit includes several features over the sta
 
 ### Preempt RT Kernel
 
-The Preempt RT Linux Kernel 6.12 is designed to offer enhanced real-time performance compared
+The Preempt RT Linux Kernel 6.17 is designed to offer enhanced real-time performance compared
 to the standard kernel:
 
 - **Reduced Latency**
@@ -138,10 +138,13 @@ The patch refines locking mechanisms, reducing the time when critical sections c
 interrupted. This improves the overall responsiveness and guarantees that the system can
 handle real-time workloads with minimal jitter.
 
-> **Note:** You can learn more about preempt Kernel and its features at the
-> [Linux Intel LTS Kernel Github](https://github.com/intel/linux-intel-lts/blob/main/README.md).
-> You can learn more about specific kernel patches related to preempt RT Kernel in the relevant
-> [SPEC file](https://github.com/open-edge-platform/edge-microvisor-toolkit/blob/3.0/SPECS/kernel/kernel.spec).
+> **Note:**
+> - Learn more about preempt Kernel and its features at the
+>   [Linux Intel LTS Kernel Github](https://github.com/intel/linux-intel-lts/blob/main/README.md).
+> - Learn more about specific kernel patches related to preempt RT Kernel in the relevant
+>   [SPEC file](https://github.com/open-edge-platform/edge-microvisor-toolkit/blob/next/SPECS/kernel/kernel.spec).
+> - The use of RT Kernel with Intel® Core™ Ultra Processors has some limitations. Refer to
+    the [Known Limitations](./emt-troubleshooting.md#known-limitations) section for more details.
 
 ### perf tool
 

docs/developer-guide/emt-system-requirements.md

@@ -58,7 +58,7 @@ and workloads. It has been validated on the following platforms:
 ## Software Requirements
 
 | Component        | Edge Microvisor Toolkit Developer Node | Edge Microvisor Toolkit (Edge Manageability Framework or Standalone Node) |
-|------------------|-------------------------|-------------------------|
-| Kernel Version   | Intel® Kernel 6.12      | Intel® Kernel 6.12      |
-| Bootloader       | GRUB                    | Systemd-boot            |
-| Update Mechanism | RPM-based with TDNF     | Image-based A/B updates |
+|------------------|----------------------------------------|---------------------------------------------------------------------------|
+| Kernel Version   | Intel® “Next” Kernel 6.17              | Intel® “Next” Kernel 6.17                                                 |
+| Bootloader       | GRUB                                   | Systemd-boot                                                              |
+| Update Mechanism | RPM-based with TDNF                    | Image-based A/B updates                                                   |

docs/developer-guide/emt-troubleshooting.md

@@ -232,4 +232,17 @@ To install from a USB device, you need to update BIOS to include the
 USB boot option and make sure USB boot has highest precedence in the
 boot order list. You also need to configure BIOS with the Platform Keys (PK) to enable
 [secure boot](./security-considerations/emt-sb-howto.md) for Edge Microvisor Toolkit.
-::::
+::::
+
+## Known Limitations
+
+### Real-time jitter and CPU spikes
+
+High variance real-time jitter and CPU spikes have been observed under specific
+configurations, listed below. The issues may result in a significant performance
+instability for real-time workloads using RAW/ISO toolkit images with RT kernel.
+
+ Platform | Processor family | Operating System | RT kernel
+--- | --- | --- | ---
+ Intel Corporation Panther Lake Client Platform | Intel(R) Core(TM) Ultra X7 358H | Edge Microvisor Toolkit | 6.17 Next
+

docs/developer-guide/get-started/deployment/emt-vm-host-setup.md

@@ -79,7 +79,7 @@ or in an Ubuntu 22.04 docker container on an Ubuntu host.
    cd <work directory>
    ```
 
-2. Extract files
+2. Extract files:
 
    ```bash
    # Extract files

docs/developer-guide/get-started/deployment/emt-vm-host-ubuntu-guest.md

@@ -143,7 +143,7 @@
    sudo reboot
    ```
 
-9. Reboot into the guest:
+9. Reboot into the guest OS:
 
    ```bash
    # after reboot check the kernel version