Implementation:LMCache LMCache LMCBlenderBuilder Get Or Create

Knowledge Sources	LMCache
Domains	Infrastructure, Inference_Optimization
Last Updated	2026-02-09 00:00 GMT

Overview

Concrete tool for creating or retrieving the CacheBlend blender singleton, provided by the LMCBlenderBuilder class.

Description

The LMCBlenderBuilder.get_or_create class method implements a singleton-per-instance_id pattern for LMCBlender instances. It creates the blender with references to the cache engine, GPU connector, and blend config. The blender internally initializes a FusedRope encoder for RoPE position recovery.

Usage

Called by the connector's _init_connector_state when enable_blending=True. Returns the existing blender if already created for this instance_id.

Code Reference

Source Location

• Repository: LMCache
• File: lmcache/v1/compute/blend/utils.py
• Lines: L25-L51

Signature

class LMCBlenderBuilder:
    @classmethod
    def get_or_create(
        cls,
        instance_id: str,
        cache_engine: LMCacheEngine,
        gpu_connector: GPUConnectorInterface,
        config: LMCacheEngineConfig,
    ) -> LMCBlender:
        """Get or create a blender instance.

        Args:
            instance_id: Engine instance ID
            cache_engine: Cache engine reference
            gpu_connector: GPU connector for KV buffer access
            config: Blend-enabled config
        Returns:
            LMCBlender instance
        """

Import

from lmcache.v1.compute.blend.utils import LMCBlenderBuilder

I/O Contract

Inputs

Name	Type	Required	Description
instance_id	str	Yes	Engine instance identifier
cache_engine	LMCacheEngine	Yes	Cache engine reference
gpu_connector	GPUConnectorInterface	Yes	GPU memory connector
config	LMCacheEngineConfig	Yes	Blend-enabled config

Outputs

Name	Type	Description
return	LMCBlender	Blender instance with FusedRope for position recovery

Related Pages

Implements Principle

• Principle:LMCache_LMCache_CacheBlend_Connector_Initialization