Update documentation with VM support for JoularJX

src/joularjx/src/SUMMARY.md

@@ -13,4 +13,5 @@
 - [Configuration Properties](./ref/configuration.md)
 - [Generated Files](./ref/generated_files.md)
 - [Integration with Systems and Tools](./ref/integration.md)
+- [Virtual machines](./ref/vm.md)
 - [How JoularJX Works](./ref/how_it_works.md)

src/joularjx/src/guide/supported_platforms.md

@@ -3,6 +3,7 @@
 JoularJX support the following platforms and operating systems:
 
 - PC/Servers using a RAPL supported Intel processor (since Sandy Bridge) or a RAPL supported AMD processor (since Ryzen), on GNU/Linux, on Windows and on macOS.
+- Virtual machines (any supported guest on any guest)
 
 The supported list of Raspberry Pi and Asus Tinker Board models are listed below.
 We support all revisions of each model lineup.
@@ -26,4 +27,5 @@ However, the model is generated and trained on a specific revision (listed betwe
 |     Windows PC/Server    |        Windows        |             Hubblo's Windows RAPL driver            |             x86, x86_64            |
 |     macOS PC    |        macOS        |             Powermetrics            |             x86_64, ARM            |
 |        Raspberry Pi       |        GNU/Linux       |             Our regression models             |             ARM            |
-|        Asus Tinker Board       |        GNU/Linux       |             Our regression models             |             ARM            |
+|        Asus Tinker Board       |        GNU/Linux       |             Our regression models             |             ARM            |
+|     Virtual Machine    |        Supported guests (Windows, Linux, macOS), any host       |             Host's architecture (RAPL, regression models, others)            |             x86, x86_64, ARM            |

src/joularjx/src/overview.md

@@ -20,6 +20,7 @@ The official website of JoularJX is: [https://www.noureddine.org/research/joular
 - Monitor power consumption of each method at runtime
 - Monitor the evolution of power consumption of each method
 - Monitor power consumption of methods' call tree and execution branches
+- Monitor energy of Java applications running in virtual machines
 - Uses a Java agent, no source code instrumentation needed
 - Uses Intel RAPL (powercap interface) for getting accurate power reading on GNU/Linux, our research-based regression models on Raspberry Pi devices, and a custom program monitor (based on Intel Power Gadget) for accurate power readings on Windows
 - Provides real-time power consumption of every method in the monitored program

src/joularjx/src/ref/vm.md

@@ -0,0 +1,30 @@
+# Virtual Machines
+
+JoularJX also works inside virtual machines.
+All its functionalities work the same inside a virtual machine as with bare metal installation.
+
+In virtual machines, JoularJX in the guest OS needs to get the power consumption of the virtual machine instance itself.
+This can only be done by installing on the host OS, a power monitoring tool (such as PowerJoular or other ones), and monitoring the power consumption of the specific guest virtual machine process.
+
+The power data of the VM process need to be written to a shared file between the host and the guest.
+Inside the guest, JoularJX will read this file continuously and use the reported power value as the power of the entire virtual machine.
+
+JoularJX is agnostic to what power tools in installed in the host and can work with any available tool that is capable of monitoring the VM process.
+
+## Use case example with JoularJX on guest and PowerJoular on host
+
+A use case example is using JoularJX on the guest OS and PowerJoular on the host OS.
+
+### In the host OS
+
+- Install [PowerJoular](https://github.com/joular/powerjoular)
+- Run PowerJoular while specifying the PID of the virtual machine of the guest OS, and writing the power data in a CSV file in overwrite mode.
+- For instance, you can run PowerJoular with the following command: ```powerjoular -p $VM_PID -o /home/vm/vm.csv```
+- Share the ```/home/vm/vm.csv``` between the host OS and the guest OS
+
+## In the guest OS
+
+- Get and compile JoularJX
+- Share the ```/home/vm/vm.csv``` between the host OS and the guest OS, potentially having a different path of the file inside the guest. For instance, ```/opt/vm/vm.csv```
+- Modify ```config.properties``` and set ``vm-power-path``` to the shared file ```/opt/vm/vm.csv```, and ```vm-power-format``` to the proper format (in this case to ```powerjoular```).
+- Start your Java application with JoularJX agent as usual.

src/powerjoular/src/guide/supported_platforms.md

@@ -38,4 +38,5 @@ We currently support the following Raspberry Pi models and Asus Tinker Board mod
 |:--------------:|:---------------------:|:-----------------------------:|:-----------------------------:|
 |        Raspberry Pi       |        GNU/Linux       |             Our regression models             |             ARM            |
 |        Asus Tinker Board       |        GNU/Linux       |             Our regression models             |             ARM            |
-|     Linux PC/Server    |        GNU/Linux        |             RAPL (using powercap), Nvidia-smi            |             x86, x86_64            |
+|     Linux PC/Server    |        GNU/Linux        |             RAPL (using powercap), Nvidia-smi            |             x86, x86_64            |
+|     Linux Virtual Machine    |        GNU/Linux guest, any host       |             Host's architecture (RAPL, regression models, others)            |             x86, x86_64, ARM            |