docs: add performance improvement section (#19300)

docs/my-website/release_notes/v1.81.0/index.md

@@ -47,6 +47,7 @@ pip install litellm==1.81.0
 
 - **Claude Code** - Support for using web search across Bedrock, Vertex AI, and all LiteLLM providers
 - **Major Change** - [50MB limit on image URL downloads](#major-change---chatcompletions-image-url-download-size-limit) to improve reliability
+- **Performance** - [25% CPU Usage Reduction](#performance---25-cpu-usage-reduction) by removing premature model.dump() calls from the hot path
 - **Deleted Keys Audit Table on UI** - [View deleted keys and teams for audit purposes](../../docs/proxy/deleted_keys_teams.md) with spend and budget information at the time of deletion
 
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@@ -155,6 +156,12 @@ This feature improves reliability by:
 
 ---
 
+## Performance - 25% CPU Usage Reduction
+
+LiteLLM now reduces CPU usage by removing premature `model.dump()` calls from the hot path in request processing. Previously, Pydantic model serialization was performed earlier and more frequently than necessary, causing unnecessary CPU overhead on every request. By deferring serialization until it is actually needed, LiteLLM reduces CPU usage and improves request throughput under high load.
+
+---
+
 ## Deleted Keys Audit Table on UI
 
 <Image img={require('../../../img/ui_deleted_keys_table.png')} />