Flexible Metadata Caching for Per-VM Memory Allocation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing memory systems in data centers inefficiently manage metadata allocation and caching, leading to increased overhead and inefficient use of memory resources due to fixed metadata configurations that do not account for varying metadata needs of different virtual machines.

Innovation Solution

Implementing a flexible metadata allocation system using the Compute Express Link (CXL) protocol, allowing dynamic allocation of metadata types such as ECC and security metadata based on the specific requirements of each virtual machine, with optional caching of extra metadata in local memory to optimize resource usage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If fixed metadata configuration is used, then system simplicity is maintained, but memory efficiency deteriorates due to inability to adapt to varying metadata needs

Engineering Contradiction:
Improvemetadata allocation flexibilityVSAvoidmetadata management complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements dynamic metadata allocation where the memory controller can adjust metadata configuration based on workload characteristics and virtual machine requirements. The system transitions from static to dynamic metadata allocation, allowing metadata size and type to be modified runtime based on detected access patterns and memory pressure conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes metadata allocation parameters dynamically by modifying the amount of metadata allocated per data block based on virtual machine identity and access patterns. Different parameter configurations are applied to different workloads, optimizing memory usage for each specific scenario.

Inventive Principle:
Principle #35Parameter changes

2Speed

If metadata is cached in local memory, then access speed is improved, but memory resource utilization deteriorates due to fixed caching allocation

Engineering Contradiction:
Improvemetadata access speedVSAvoidmemory resource utilization
Core Design Contradiction:
SpeedVSQuantity of substance

Solution Approach 1:

The patent implements dynamic caching where the amount of metadata cached in local memory is adjusted based on system conditions. The memory controller monitors cache hit rates and memory pressure, dynamically allocating cache space to metadata when beneficial and releasing it when memory resources are constrained.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system dynamically changes cache allocation parameters by adjusting the size of metadata cache based on workload characteristics and available memory resources. Cache configuration is modified runtime to optimize the balance between access speed and memory utilization.

Inventive Principle:
Principle #35Parameter changes

3Loss of energy

If uniform metadata allocation is applied to all virtual machines, then system simplicity is maintained, but overhead increases due to allocating unnecessary metadata to some VMs

Engineering Contradiction:
Improvememory overheadVSAvoidallocation management complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The patent applies different metadata allocation strategies to different virtual machines based on their specific requirements. The memory controller identifies VM characteristics and allocates appropriate metadata configurations locally to each VM, avoiding uniform allocation of excessive metadata to all VMs.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The system dynamically changes metadata allocation parameters for each virtual machine based on detected workload patterns and VM identity. Allocation size and type are adjusted per-VM to minimize overhead while maintaining necessary functionality.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS20260038548A1Flexible metadata allocation and caching
Publication Date: 2026.02.05 RAMBUS INC
  • US20260038548A1 patent drawing
  • US20260038548A1 patent drawing
  • US20260038548A1 patent drawing

AI summary

An apparatus and method for flexible metadata allocation and caching. In one embodiment of the method first and second requests are received from first and second applications, respectively, wherein the requests specify a reading of first and second data, respectively, from one or more memory devices. The circuit reads the first and second data in response to receiving the first and second requests. Receiving first and second metadata from the one or more memory devices in response to receiving the first and second requests. The first and second metadata correspond to the first and second data, respectively. The first and second data are equal in size, and the first and second metadata are unequal in size.