Files
MultiforaDB/tests/e2e/README.md
Aleksey Shakhmatov d4c9b04f21 rename project to MultiforaDB
Prose and benchmark tables use MultiforaDB; the binary, the CLI usage
line, the log-message prefix and the default database file use
multiforadb.

Two consequences worth noting:

- build.zig.zon's fingerprint is derived from the package name, so it
  had to change with it (Zig refuses to build otherwise). A consumer
  pinning this package by fingerprint needs updating.
- the default --db path is now multiforadb.log, and getCmdLineOpts
  reports it as dbpath. An existing mongo-lite.log has to be passed
  explicitly with --db.

The e2e harness abbreviated the old name as ML_; that is now MFDB_,
including the documented ML_BIN override (MFDB_BIN) and the scratch
file names. MD_ (mongod) is untouched.

compare-run.sh spawned the server by absolute path under a
sandbox/mongo-lite directory that no longer exists; that block already
runs from tests/e2e, so it uses a relative path now.

The archived reports under tests/e2e/results/ keep the old name: they
record what the old binary measured.
2026-08-03 12:35:01 +03:00

116 lines
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Markdown

# End-to-end tests with the official MongoDB Node.js driver
These exercise MultiforaDB from a real driver over TCP: full CRUD, query
operators, aggregation, error codes, concurrent clients, crash recovery, and
the whole lifecycle including server restarts.
## Setup
```sh
cd tests/e2e
npm init -y >/dev/null
npm install mongodb
```
## Run
Most suites expect a server running on port 27020:
```sh
zig build
zig-out/bin/multiforadb --port 27020 --db /tmp/mfdb-e2e.log --ttl-sweep-secs 1 &
node tests/e2e/e2e.js # CRUD + operators + aggregate + errors (29 checks)
node tests/e2e/e2e2.js concurrent # 8 clients: 4 writers + 4 readers (2 checks)
node tests/e2e/e2e2.js crash-a # write 50 docs, then kill -9 the server
node tests/e2e/e2e2.js crash-b # restart and verify all 50 survived
node tests/e2e/e2e3.js # secondary indexes: unique/sparse/compound (16 checks)
node tests/e2e/e2e4.js # TTL indexes: expiry + rejected specs (15 checks)
```
`e2e4.js` needs the server started with `--ttl-sweep-secs 1` (the default is
60 seconds); the other suites do not care about the flag.
`e2e6.js` is the full-lifecycle suite and is self-contained: it spawns its
own server on port 27220 with a fresh log, runs the whole feature surface,
restarts the server twice (graceful SIGTERM, then kill -9 mid-write) and
verifies everything survived:
```sh
node tests/e2e/e2e6.js # 73 checks, ~15 s, needs no running server
E2E6_PORT=27300 node tests/e2e/e2e6.js # different port if 27220 is taken
```
Rebuild with `zig build` after any change under `src/` before restarting the
server: `zig build test` compiles the test binary only and leaves
`zig-out/bin/multiforadb` stale, so the suites keep running against the old
rules and report failures that the source no longer explains.
`e2e2.js concurrent` is safe to repeat against a running server (it drops its
collection first); `crash-a`/`crash-b` are two halves of one scenario.
## Multi-GB collections: `big.js`
`big.js` is a load harness, not a pass/fail suite: it spawns a server, bulk
loads up to ~5 GB, and reports insert throughput, the compaction behavior,
server RSS, per-operation latencies, reopen (replay) time, and kill -9
durability.
```sh
node tests/e2e/big.js --quick # 268 MB smoke run
node tests/e2e/big.js --size 5g --doc-size 128k --oid --batch 200 \
--compact-threshold 2g # ~5 GB, 40k docs
```
Options: `--size`/`--doc-size`/`--batch` (k/m/g suffixes), `--oid`
(ObjectId `_id`s — see below), `--index <field>` (secondary index before
loading), `--compact-threshold <bytes>` (passed to the server),
`--port`, `--keep` (keep the db file).
Measured behavior (all documented in the top-level README):
- **Build in ReleaseFast** — `zig build` defaults to it; a Debug server is
10-200x slower on every path.
- **Insert throughput collapses under the default 16 MiB compaction
threshold**: every ~16 MB of writes rewrites the whole log with one fsync
per record (O(n²) total). With `--compact-threshold 2g` the rate stays
flat (hundreds of MB/s at 128 KB docs in ReleaseFast). Raise the
threshold for bulk loads.
- **`findOne({_id})` is O(1) only for ObjectId `_id`s.** Integer `_id`s are
serialization-ambiguous (int32/int64/double compare equal but hash
differently), so the docs-map fast path is skipped and every lookup is a
full scan. Use the driver's default ObjectId ids on big collections.
- **The engine holds everything in RAM**: ~1-1.2x the data size at 128 KB
docs (more at 16 KB docs, where per-document arena overhead dominates).
A 5 GB collection needs roughly 6-7 GB of RAM.
- Reopen of a 5 GB log replays in ~10 s (ReleaseFast); every committed
write survives kill -9.
## Comparing against real MongoDB: `compare.js` + `compare-run.sh`
```sh
bash tests/e2e/compare-run.sh [size] [doc-size] # e.g. 1g 16k
```
Starts mongod (`brew install mongodb-community`) on :27018 and MultiforaDB
on :27019, runs the same driver workload against each (durable writes:
MultiforaDB fsyncs per command, mongod runs with `j: true`), measures kill -9
reopen for both, and prints a side-by-side table. `compare.js` alone runs
one side (see its `--help`-style header comment).
### Iteration-to-iteration comparison: `bench-run.sh` + `concurrent.js`
```sh
bash tests/e2e/bench-run.sh [size] [doc-size] ["clients..."] # e.g. 1g 16k "1 4 8 16 32"
```
Runs the main suite (`compare-run.sh`) plus a concurrent durable-write
comparison (`concurrent.js`, N clients each doing sequential `insertOne`
with `{w:1, j:true}` — the group-commit path under real contention), then
writes a machine-readable, versioned report to
`tests/e2e/results/bench-<timestamp>.txt` and prints a diff of the
MultiforaDB numbers against the previous run (`results/bench-latest.txt`).
The report has `[main]` / `[concurrency]` / `[meta]` sections with
`name<TAB>value` rows; `bench-run.sh 1g 16k` reproduces the phase8 gate
(see `results/phase8.txt`).