proxy: add PYROSCOPE_SAMPLE_RATE env, use verbose logging, fix int type

- Add optional PYROSCOPE_SAMPLE_RATE env (integer, no default)
- Pass sample_rate to pyroscope.configure() as int for pyroscope-io
- Replace print with verbose_proxy_logger (info/warning)
- Document PYROSCOPE_SAMPLE_RATE in config_settings.md

docs/my-website/docs/proxy/config_settings.md

@@ -775,6 +775,7 @@ router_settings:
 | LITELLM_ENABLE_PYROSCOPE | If true, enables Pyroscope CPU profiling. Profiles are sent to PYROSCOPE_SERVER_ADDRESS. Off by default. See [Pyroscope profiling](/proxy/pyroscope_profiling).
 | PYROSCOPE_APP_NAME | Application name reported to Pyroscope. Required when LITELLM_ENABLE_PYROSCOPE is true. No default.
 | PYROSCOPE_SERVER_ADDRESS | Pyroscope server URL to send profiles to. Required when LITELLM_ENABLE_PYROSCOPE is true. No default.
+| PYROSCOPE_SAMPLE_RATE | Optional. Sample rate for Pyroscope profiling (integer). No default; when unset, the pyroscope-io library default is used.
 | LITELLM_MASTER_KEY | Master key for proxy authentication
 | LITELLM_MODE | Operating mode for LiteLLM (e.g., production, development)
 | LITELLM_NON_ROOT | Flag to run LiteLLM in non-root mode for enhanced security in Docker containers

litellm/proxy/proxy_server.py

@@ -5561,9 +5561,10 @@ class ProxyStartupEvent:
         Off by default. Enable with LITELLM_ENABLE_PYROSCOPE=true.
         Requires: pip install pyroscope-io
         Sends profiles to PYROSCOPE_SERVER_ADDRESS (default http://localhost:4040).
+        Optional: PYROSCOPE_SAMPLE_RATE (float, no default) to set the sample rate.
         """
         if not get_secret_bool("LITELLM_ENABLE_PYROSCOPE", False):
-            print(  # noqa: T201
+            verbose_proxy_logger.info(
                 "LiteLLM: Pyroscope profiling is disabled (set LITELLM_ENABLE_PYROSCOPE=true to enable)."
             )
             return
@@ -5588,17 +5589,31 @@ class ProxyStartupEvent:
             )
             if env_name:
                 tags["environment"] = env_name
-            pyroscope.configure(
-                app_name=app_name,
-                server_address=server_address,
-                tags=tags if tags else None,
-            )
-            print(  # noqa: T201
+            sample_rate_env = os.getenv("PYROSCOPE_SAMPLE_RATE")
+            configure_kwargs = {
+                "app_name": app_name,
+                "server_address": server_address,
+                "tags": tags if tags else None,
+            }
+            if sample_rate_env is not None:
+                try:
+                    # pyroscope-io expects sample_rate as an integer
+                    configure_kwargs["sample_rate"] = int(float(sample_rate_env))
+                except (ValueError, TypeError):
+                    raise ValueError(
+                        "PYROSCOPE_SAMPLE_RATE must be a number, got: "
+                        f"{sample_rate_env!r}"
+                    )
+            pyroscope.configure(**configure_kwargs)
+            msg = (
                 f"LiteLLM: Pyroscope profiling started (app_name={app_name}, server_address={server_address}). "
                 f"View CPU profiles at the Pyroscope UI and select application '{app_name}'."
             )
+            if "sample_rate" in configure_kwargs:
+                msg += f" sample_rate={configure_kwargs['sample_rate']}"
+            verbose_proxy_logger.info(msg)
         except ImportError:
-            print(  # noqa: T201
+            verbose_proxy_logger.warning(
                 "LiteLLM: LITELLM_ENABLE_PYROSCOPE is set but the 'pyroscope-io' package is not installed. "
                 "Pyroscope profiling will not run. Install with: pip install pyroscope-io"
             )