Implicit-storing and redundant-encoding-of-attribute information in error-correction-codes

Abstract

This paper proposes implicit-storing to extend the logical capacity of a memory array without increasing its physical capacity by leveraging the array's error-correction-codes to infer the implicitly stored bits. Implicit-storing is related to error-code-tagging, a technique that distinguishes between faults in data and invariant attributes of a location when the attributes are not stored in the memory array but are encoded in the error-correction-codes. Both error-code-tagging and implicit-storing cause a code-strength reduction due to their encoding of additional information in the code meant to only protect data.Redundant-encoding-of-attributes is introduced to improve the strength of a code by encoding same information in multiple codewords in a cache or memory. We demonstrate how EREA and IREA, two derivatives of redundant-encoding, alleviate the code-strength reduction experienced by errorcode-tagging and implicit-storing respectively.Implementing the proposed methods requires minor modifications in the encoding and decoding logic of the baseline error-correction scheme used in this work. The paper discusses several uses of the proposed schemes to help demonstrate their usefulness.

MUSE: Multi-Use Error Correcting Codes

“…MUSE ECC was developed to be able to support both reliability and security. Prior work in the area of co-designing security and reliability assumes standard ChipKill or SEC-DED code [21,44,45] and those codes do not provide a way to extract more state for security or performance features or reduce the amount of storage for reliability which are key contributions of MUSE ECC. MUSE ECC is also orthogonal to architectural optimizations such as Frugal ECC [30], Virtualized ECC [52], and COP [37].…”

Hi-fi playback

“…Recent research on error correction code (ECC) focuses on how to reduce the overhead, such as VS-ECC [4], CPPC [21], little-space ECC [31], etc. The work explores trade-off between reliability and area/performance/energy.…”