Documentation updates for AMDSMI_GPU_METRICS_CACHE_MS (#564)

Signed-off-by: Maisam Arif <Maisam.Arif@amd.com>

docs/how-to/amdsmi-cli-tool.md

@@ -75,6 +75,20 @@ usage information. See [Commands](#cmds).
 For more detailed version information, use `amd-smi version`.
 ```
 
+Environment variables:
+
+You can set one or more variables in front of any `amd-smi` invocation. For example:
+
+```shell-session
+AMDSMI_GPU_METRICS_CACHE_MS=200 amd-smi metric
+```
+
+Current Variables:
+
+```{note}
+AMDSMI_GPU_METRICS_CACHE_MS - Controls the internal GPU metrics cache duration (ms). Default 100, set to 0 to disable.
+```
+
 (cmds)=
 ## Commands
 

docs/how-to/amdsmi-cpp-lib.md

@@ -21,6 +21,12 @@ variable to the directory containing ``librocm_smi64.so`` (usually
 ``/opt/rocm/lib``) or by passing the ``-lamd_smi`` flag to the compiler.
 ```
 
+```{note}
+The environment variable ``AMDSMI_GPU_METRICS_CACHE_MS`` may be set to
+control the internal GPU metrics cache duration (ms). 
+Default 1, set to 0 to disable.
+```
+
 ```{seealso}
 Refer to the [C++ library API reference](../reference/amdsmi-cpp-api.md).
 ```

docs/how-to/amdsmi-py-lib.md

@@ -39,6 +39,30 @@ variable to the directory containing ``librocm_smi64.so`` (usually
 ``/opt/rocm/lib``) or by passing the ``-lamd_smi`` flag to the compiler.
 ```
 
+```{note}
+The environment variable ``AMDSMI_GPU_METRICS_CACHE_MS`` may be set to
+control the internal GPU metrics cache duration (ms). 
+Default 1, set to 0 to disable.
+
+You can apply it in one of two ways:
+
+1. In Python code (before the AMDSMI library loads):
+```
+
+```python
+import os
+os.environ["AMDSMI_GPU_METRICS_CACHE_MS"] = "200"
+from amdsmi import *
+```
+
+```{note}
+2. On the shell when invoking Python:
+```
+
+```shell
+AMDSMI_GPU_METRICS_CACHE_MS=200 python tools/amdsmi_quick_start.py
+```
+
 To get started, the `amdsmi` folder should be copied and placed next to
 the importing script. Import it as follows: