RightMV
← System overview

STORAGE / COMMUNITY

UberHash

RightMV's lightweight storage engine for capable, portable Community systems.

01 / DESIGN

How UberHash stores data.

UberHash stores each MultiValue file as append-oriented data with a hash-bucket index. DISK mode keeps the index on storage, while HOT mode can retain index structures in memory. Pointer, bucket-writer and stream-buffer caches bound repeated I/O.

AVAILABILITYCommunity storage provider.
  1. 01Item ID
  2. 02Stable hash
  3. 03Modulo bucket
  4. 04Key match
  5. 05Append-oriented record data

02 / TRADE-OFFS

Choose the engine for the workload.

Storage engines balance memory, I/O, recovery, concurrency and operational complexity. These profiles show where each engine fits.

STRENGTHS

  • Fast direct item lookup
  • Native MultiValue modulo model
  • Portable account and file layout
  • Integrated record locks and secondary indexes

WEAKNESSES

  • Modulo selection affects collision depth
  • HOT indexes trade memory for speed
  • Filesystem latency directly affects operations
  • Distributed lock files require sensible TTL and heartbeat values

03 / ABILITIES

What it provides.

UberHash is a primary Community storage engine for lightweight and portable deployments, including IES on small instances.

01

DATA and DICT areas

02

DISK and HOT file modes

03

Record-lock ownership with heartbeat refresh

04

Secondary-index maintenance

BEST FIT

  • Community systems
  • Portable environments
  • Modest infrastructure
  • Development and evaluation

CORE CAPABILITIES

  • Lightweight storage
  • ExecutionContext integration
  • Locking and indexes
  • export-all and import-all portability

CONFIGURATION

  • MVDB_UBERHASH_DATA_ROOT
  • MVDB_UBERHASH_LOCK_TTL_MS
  • MVDB_UBERHASH_LOCK_HEARTBEAT_MS
  • MVDB_UBERHASH_POINTER_CACHE_ENTRIES
  • MVDB_UBERHASH_BUCKET_WRITER_CACHE_ENTRIES