[Rocprofiler-systems]: Documentation addition for xgmi and pcie metrics feature (#1798)

* Documentation addition for xgmi and pcie metrics feature Add documentation to provide details about How to get collect XGMI and PCIe interconnect metrics. * Apply suggestions from code review Co-authored-by: Pratik Basyal <pratik.basyal@amd.com> * Update projects/rocprofiler-systems/CHANGELOG.md Co-authored-by: Pratik Basyal <pratik.basyal@amd.com> * Update projects/rocprofiler-systems/CHANGELOG.md Co-authored-by: Pratik Basyal <pratik.basyal@amd.com> --------- Co-authored-by: Pratik Basyal <pratik.basyal@amd.com> Co-authored-by: David Galiffi <David.Galiffi@amd.com>
2025-11-17 18:34:28 -05:00
commit f6183e3563
@@ -8,6 +8,8 @@ Full documentation for ROCm Systems Profiler is available at [https://rocm.docs.

 ### Added

+- Profiling and metric collection capabilities for XGMI and PCIe data.
+- How-to document for XGMI and PCIe sampling and monitoring.
 - Added a `ROCPROFSYS_PERFETTO_FLUSH_PERIOD_MS` configuration setting to set the flush period for Perfetto traces. The default value is 10000 ms (10 seconds).
 - Added fetching of the `rocpd` schema from rocprofiler-sdk-rocpd

@@ -64,9 +64,11 @@ The documentation source files reside in the [`/docs`](/docs) folder of this rep
  - Utilization
  - VCN Utilization
  - JPEG Utilization
+  - XGMI interconnect metrics (link width, link speed, read/write data)
+  - PCIe metrics (link width, link speed, bandwidth)

 > [!NOTE]
-> The availability of VCN and JPEG engine utilization depends on device support for different ASICs. If unsupported, all values for VCN_ACTIVITY and JPEG_ACTIVITY will be reported as N/A in the output of `amd-smi metric --usage`.
+> The availability of VCN, JPEG, XGMI, and PCIe metrics depends on device support, system topology, and GPU architecture. If unsupported, all values will be reported as N/A in the output of `amd-smi metric --usage`.

 ### CPU metrics

@@ -62,7 +62,12 @@ GPU metrics
  * Utilization
  * VCN activity
  * JPEG activity
-    Note: The availability of VCN and JPEG engine activity depends on device support for different ASICs. If unsupported, all values for VCN_ACTIVITY and JPEG_ACTIVITY will be reported as N/A in the output of amd-smi metric--usage.
+  * XGMI interconnect metrics (link width, link speed, read/write data)
+  * PCIe metrics (link width, link speed, bandwidth)
+  
+  .. note::
+  
+  The availability of VCN, JPEG, XGMI, and PCIe metrics depends on device support and system topology. If unsupported, values will be reported as ``N/A`` in the output of ``amd-smi metric --usage``.

 CPU metrics
 ========================================
@@ -252,7 +252,7 @@ For example, the following is a valid configuration:

   ROCPROFSYS_AMD_SMI_METRICS=busy,temp,power,vcn_activity,mem_usage

-Supported values for ``ROCPROFSYS_AMD_SMI_METRICS`` are: ``busy``, ``temp``, ``power``, ``vcn_activity``, ``mem_usage``, ``jpeg_activity``.
+Supported values for ``ROCPROFSYS_AMD_SMI_METRICS`` are: ``busy``, ``temp``, ``power``, ``vcn_activity``, ``mem_usage``, ``jpeg_activity``, ``xgmi``, ``pcie``.

 API tracing is configured with the ``ROCPROFSYS_ROCM_DOMAINS`` setting. The domains are used to filter the events that are captured during profiling.
 Supported values for this setting are those supported by ROCprofiler-SDK, which are returned by the API ``get_callback_tracing_names()`` and ``get_buffer_tracing_names()``. See the `ROCprofiler-SDK developer API documentation <https://rocm.docs.amd.com/projects/rocprofiler-sdk/en/latest/_doxygen/rocprofiler-sdk/html/>`_ to learn more about ROCprofiler-SDK APIs.
@@ -0,0 +1,173 @@
+.. meta::
+   :description: ROCm Systems Profiler XGMI and PCIe metrics sampling and monitoring
+   :keywords: rocprof-sys, rocprofiler-systems, ROCm, tips, how to, profiler, tracking, XGMI, PCIe, GPU connectivity, AMD
+
+***********************************************
+XGMI and PCIe metrics sampling and monitoring
+***********************************************
+
+`ROCm Systems Profiler <https://github.com/ROCm/rocm-systems/tree/develop/projects/rocprofiler-systems>`_ supports
+sampling of XGMI and PCIe interconnect metrics. It allows you to gather key performance metrics for
+GPU-to-GPU communication via XGMI links, and CPU-to-GPU communication via PCIe links. This information can be used
+to optimize multi-GPU workloads, identify communication bottlenecks, and analyze data transfer efficiency
+in high-performance computing applications.
+
+Sampling support
+=================
+
+Sampling of XGMI and PCIe interconnect metrics is supported by leveraging `AMD SMI <https://rocm.docs.amd.com/projects/amdsmi/en/latest/>`_ which provides the interface for GPU metric collection. Follow the steps:
+
+1. Set the ``ROCPROFSYS_USE_AMD_SMI`` environment variable to enable GPU metric collection:
+
+.. code-block:: shell
+
+  export ROCPROFSYS_USE_AMD_SMI=true
+
+2. Update the ``ROCPROFSYS_AMD_SMI_METRICS`` variable to collect the XGMI and PCIe metrics. The default value is:
+
+.. code-block:: shell
+
+  ROCPROFSYS_AMD_SMI_METRICS=busy,temp,power,mem_usage
+
+To include XGMI and PCIe metrics, update it to:
+
+.. code-block:: shell
+
+  ROCPROFSYS_AMD_SMI_METRICS=busy,temp,power,mem_usage,xgmi,pcie
+
+Alternatively, you can use the following to collect all available GPU metrics:
+
+.. code-block:: shell
+
+  ROCPROFSYS_AMD_SMI_METRICS=all
+
+XGMI metrics
+------------
+
+XGMI (AMD Infinity Fabric™ XGMI) provides high-bandwidth, low-latency GPU-to-GPU interconnects in multi-GPU systems. The following XGMI metrics are collected:
+
+- **XGMI Link Width**: The number of active XGMI links between GPUs
+- **XGMI Link Speed**: The speed of XGMI links (in GT/s)
+- **XGMI Read Data**: Accumulated data read through each XGMI link (in KB)
+- **XGMI Write Data**: Accumulated data written through each XGMI link (in KB)
+
+These metrics help identify GPU-to-GPU communication patterns and bandwidth utilization in multi-GPU workloads.
+
+.. note::
+
+   XGMI metrics are only available on systems with multiple GPUs connected via XGMI links. 
+   The availability depends on the system topology and GPU architecture. If unsupported or not 
+   available, the values will be reported as N/A in the output.
+
+PCIe metrics
+------------
+
+PCIe (PCI Express) provides the connection between the CPU and GPU. The following PCIe metrics are collected:
+
+- **PCIe Link Width**: The number of PCIe lanes currently active
+- **PCIe Link Speed**: The current PCIe link generation and speed (e.g., Gen3, Gen4, Gen5)
+- **PCIe Bandwidth Accumulated**: Total bandwidth accumulated over time (in MB)
+- **PCIe Bandwidth Instantaneous**: Instantaneous bandwidth at the time of sampling (in MB/s)
+
+These metrics help analyze CPU-to-GPU data transfer efficiency and identify PCIe bottlenecks.
+
+Using TransferBench for testing
+================================
+
+For testing and benchmarking GPU connectivity, you can use the `TransferBench <https://rocm.docs.amd.com/projects/TransferBench/en/latest/index.html>`_.
+TransferBench is a benchmarking utility designed to measure the performance of simultaneous data transfers between user-specified devices, such as CPUs and GPUs.
+For this example, TransferBench is used to profile XGMI and PCIe traffic for analysis.
+
+1. Source the ROCm Systems Profiler Environment using:
+
+.. code-block:: shell
+
+   source /opt/rocprofiler-systems/share/rocprofiler-systems/setup-env.sh
+
+Alternatively, if you are using modules, use:
+
+.. code-block:: shell
+
+   module use /opt/rocprofiler-systems/share/modulefiles
+
+2. Generate and configure the profiler config file.
+
+.. code-block:: shell
+
+   rocprof-sys-avail -G $HOME/.rocprofsys.cfg -F txt
+   export ROCPROFSYS_CONFIG_FILE=$HOME/.rocprofsys.cfg
+
+Edit ``.rocprofsys.cfg`` with the following settings:
+
+.. code-block:: shell
+
+  ROCPROFSYS_USE_AMD_SMI     = true
+  ROCPROFSYS_AMD_SMI_METRICS = busy,temp,power,mem_usage,xgmi,pcie
+  ROCPROFSYS_ROCM_DOMAINS    = hip_runtime_api,memory_copy,hsa_api
+
+3. Profile the TransferBench application.
+
+.. code-block:: shell
+
+  rocprof-sys-sample -PTHD -- ./TransferBench a2a
+
+.. note::
+
+   Refer to these steps to `Install and build TransferBench <https://rocm.docs.amd.com/projects/TransferBench/en/latest/install/install.html#install-transferbench>`_.
+
+At the end of the run, a similar message appears::
+
+  [rocprofiler-systems][964294][perfetto]> Outputting '/home/demo/rocprofsys-transferBench-output/2025-04-25_15.52/perfetto-trace-964294.proto'
+  (3124.52 KB / 3.12 MB / 0.00 GB)... Done
+
+
+To view the generated ``.proto`` file in the browser, open the
+`Perfetto UI page <https://ui.perfetto.dev/>`_. Then, click on
+``Open trace file`` and select the ``.proto`` file. In the browser, you can visualize the XGMI and PCIe metrics.
+
+.. image:: ../data/rocprof-sys-xgmi.png
+   :alt: Visualization of a performance graph in Perfetto with XGMI tracks
+
+.. image:: ../data/rocprof-sys-pcie.png
+   :alt: Visualization of a performance graph in Perfetto with PCIe tracks
+
+The visualization will show:
+
+- **XGMI Read Data** and **XGMI Write Data** tracks showing data transfer through XGMI links over time
+- **XGMI Link Width** and **XGMI Link Speed** tracks showing link configuration
+- **PCIe Bandwidth** tracks showing CPU-to-GPU data transfer rates
+- **PCIe Link Width** and **PCIe Link Speed** tracks showing PCIe link configuration
+
+
+Tips for effective profiling
+=============================
+
+1. **Multi-GPU workloads**: XGMI metrics are most useful when profiling applications that use multiple GPUs and transfer data between them.
+
+2. **Sampling frequency**: Adjust the sampling frequency using ``ROCPROFSYS_PROCESS_SAMPLING_FREQ`` (default is 50Hz) to capture more or fewer samples based on your analysis needs.
+
+3. **Focus on specific metrics**: If you only need XGMI or PCIe metrics, you can specify just those:
+
+   .. code-block:: shell
+
+     ROCPROFSYS_AMD_SMI_METRICS=xgmi  # Only XGMI metrics
+     ROCPROFSYS_AMD_SMI_METRICS=pcie  # Only PCIe metrics
+
+4. **Combine with API tracing**: For detailed analysis, combine XGMI/PCIe metrics with HIP/HSA API tracing to correlate data transfers with application behavior:
+
+   .. code-block:: shell
+
+     ROCPROFSYS_ROCM_DOMAINS=hip_runtime_api,memory_copy,kernel_dispatch,hsa_api
+
+Exploring available metrics
+============================
+
+To explore all supported metrics and domains, use the following commands:
+
+.. code-block:: shell
+
+  rocprof-sys-avail --all                    # Show all available options
+  rocprof-sys-avail -bd -r AMD_SMI_METRICS   # Show AMD SMI metrics
+  rocprof-sys-avail -bd -r ROCM_DOMAINS      # Show ROCm tracing domains
+
+For more details on ROCm Systems Profiler configuration, refer to the `configuration guide <configuring-runtime-options.html>`_.
@@ -41,6 +41,7 @@ profiling, how it supports performance analysis, and how to leverage its capabil
      * :doc:`Profiling Python scripts <./how-to/profiling-python-scripts>`
      * :doc:`Network performance profiling <./how-to/nic-profiling>`
      * :doc:`VCN and JPEG sampling and tracing <./how-to/vcn-jpeg-sampling>`
+      * :doc:`XGMI and PCIe metrics monitoring <./how-to/xgmi-pcie-sampling>`

    * :doc:`Understanding the output <./how-to/understanding-rocprof-sys-output>`
    * :doc:`Using the ROCm Systems Profiler API <./how-to/using-rocprof-sys-api>`
@@ -37,6 +37,8 @@ subtrees:
          title: Network performance profiling
        - file: how-to/vcn-jpeg-sampling.rst
          title: VCN and JPEG sampling and tracing
+        - file: how-to/xgmi-pcie-sampling.rst
+          title: XGMI and PCIe metrics monitoring
    - file: how-to/understanding-rocprof-sys-output.rst
      title: Understanding the output
    - file: how-to/using-rocprof-sys-api.rst