unified_bench

unified_bench

Side-by-side benchmarks for HashDB, BTreeOnHashDB, TreeDB (cached), TreeDBBackend (uncached), Badger, and LevelDB.

Run

• Build: make unified-bench (writes bin/unified-bench)
• Run: ./bin/unified-bench
• Or: go run ./cmd/unified_bench

Reproducibility

• Randomized tests use a per-test PRNG derived from -seed so every DB sees the same random key/query sequence.
• The chosen seed is printed to stderr at startup.

Tests

• write_seq — Sequential Write
• write_rand — Random Write
• batch_write — Batch Write
• batch_random — Batch Random
• batch_delete — Batch Delete
• delete_rand — Random Delete
• read_rand — Random Read
• full_scan — Full Scan (iterate the full keyspace)
• prefix_scan — Prefix Scan (range scans over [start,end))
  • Aliases: scan → full_scan, range_scan → prefix_scan

Common flags

• -dbs (all or CSV): hashdb,btree,treedb,treedbbackend,badger,leveldb
• -test (all or CSV): see list above
• -keys number of keys (default 100000)
• -keycounts comma-separated key counts to sweep over (overrides -keys)
• -keyscale generate keycounts by scale: log10 or doubling (uses -keys-min / -keys-max)
• -valsize value size in bytes (default 128)
• -batchsize batch size (default 1000)
• -range-queries number of prefix/range queries (default 200)
• -range-span number of keys per range (default 100)
• -treedb-flush-threshold TreeDB (cached) flush threshold in bytes (default 64MB)
• -treedb-max-queued-memtables TreeDB (cached) max queued immutable memtables before applying backpressure flush (0=default, <0=disable)
• -treedb-slowdown-backlog-seconds TreeDB (cached) start backpressure when queued backlog exceeds this many seconds of flush work
• -treedb-stop-backlog-seconds TreeDB (cached) block writers when queued backlog exceeds this many seconds of flush work
• -treedb-max-backlog-bytes TreeDB (cached) absolute cap on queued backlog bytes
• -treedb-writer-flush-max-memtables TreeDB (cached) max memtables a writer will help flush per op
• -treedb-writer-flush-max-ms TreeDB (cached) max time (ms) a writer will help flush per op
• -treedb-iter-debug print prefix scan iterator timing + debug stats
• -treedb-iter-debug-limit max per-query debug lines to print (default 20)
• -treedb-bg-vacuum-interval TreeDB: background index vacuum interval (0=disabled)
• -treedb-bg-vacuum-span-ppm TreeDB: background index vacuum span ratio threshold (ppm), 0=default
• -treedb-allow-unsafe TreeDB: allow unsafe durability/integrity options (required for unsafe toggles)
• -seed PRNG seed for randomized tests (default 1; 0 = time-based)
• -keep keep temp DB directories after run
• -settle-before-scans close+reopen DBs before full_scan/prefix_scan to measure scan performance on a “settled” (fully flushed) state
• -progress live table updates to stderr (default true)
• -format output format: table or markdown
• -cpuprofile, -blockprofile, -mutexprofile, -trace write profiling artifacts to files
• -max-wall abort the run if wall time exceeds this duration (guardrail; 0 = disabled)
• -max-rss-mb abort the run if RSS exceeds this many MiB (guardrail; 0 = disabled; Linux-only)
• -checkpoint-between-tests force a best-effort durability checkpoint between tests (DBs that support Checkpoint())
• -checkpoint-every-ops force a best-effort durability checkpoint every N ops during write-heavy tests (DBs that support Checkpoint())
• -checkpoint-every-bytes force a best-effort durability checkpoint every N approx bytes during write-heavy tests (DBs that support Checkpoint())
• -suite named suite:
  • readme — generates the README graphs + sweep tables
  • churn — churn + settled scans (treedb,leveldb)
  • churnvacuum — churn + settled scans, then VACUUM and scan again
  • churnmaint — churn + settled scans, then slab compaction + VACUUM and scan again
  • flushthrash — forces a small TreeDB flush threshold; catches flush thrash / runaway backlog regressions
  • bigkeys_guard — small TreeDB flush threshold + large keycount, with wall/RSS caps for CI guardrails
  • longmix — long-ish mixed workload + settle boundary with fragmentation reports
  • sload_readheavy — settled point reads with pointer values (exercises slab reads) + forkchoice-style batch commits
• -outdir output directory for suite artifacts (plots/images; used by -suite readme)