Page Table Metadata Pointer Extraction

Solution Overview

Problem

Existing methods for associating metadata with addresses incur significant latency and memory overhead due to the need for independent metadata trees, which are costly to maintain and require additional memory allocations.

Innovation Solution

The approach leverages the existing page table structure to locate metadata by extracting and combining portions from multiple page table entries to form a pointer, allowing efficient access to metadata tables without the need for a separate metadata tree, thereby reducing memory requirements and latency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an independent metadata tree structure is used to locate metadata, then metadata can be stored and retrieved, but significant latency and memory overhead are incurred

Engineering Contradiction:

Improvemetadata retrieval capabilityVSAvoidlatency

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent merges the metadata storage structure with the existing page table structure by using the page table entries to store portions of a pointer to metadata. This eliminates the need for a separate independent metadata tree, combining two functions into one existing structure thereby reducing latency and memory overhead while maintaining metadata retrieval capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The page table structure is given multi-functionality by using it not only for address translation but also for storing pointer portions to metadata. This universal use of the existing page table structure eliminates the need for dedicated metadata storage structures, reducing both latency and memory requirements while preserving full metadata access capability

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If an independent metadata tree structure is used to locate metadata, then metadata can be stored and retrieved, but additional memory allocations and maintenance overhead are required

Engineering Contradiction:

Improvemetadata storage capabilityVSAvoidmemory overhead

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the metadata storage structure with the existing page table structure by using the page table entries to store portions of a pointer to metadata. This eliminates the need for a separate independent metadata tree, combining two functions into one existing structure thereby reducing latency and memory overhead while maintaining metadata retrieval capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The existing page table structure serves itself by storing pointer portions within its own entries. This self-service approach eliminates the need for external metadata storage structures and their associated memory overhead and maintenance complexity, as the page table already exists and is being used for address translation anyway

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS11334499B2Method for locating metadata

Publication Date: 2022.05.17 ARM LTD

AI summary

A method for locating metadata associated with a first address. The method comprises: accessing a page table structure, a page table entry of said page table structure providing address translation data for use in an address translation process for translating said first address into a second address; extracting (906) portions of at least two page table entries in the page table structure, determining (906) a pointer to a metadata table from said portions, and using (908) the pointer to locate from the metadata table target metadata associated with the first address.