| After loading and initial maintenance |    SQLite |                                  PostgreSQL |
| ------------------------------------- | --------: | ------------------------------------------: |
| Messages                              | 4,360,000 |                                   4,360,000 |
| Database size, decimal GB             |     8.008 |                                      14.324 |
| Database engine                       |    3.53.3 |                                       17.11 |
| Full-text implementation              |      FTS5 | `tsvector` with `simple` dictionary and GIN |

## Existing-database startup

| Single observed provider initialization            |     SQLite | PostgreSQL |
| -------------------------------------------------- | ---------: | ---------: |
| Enable duration                                    | 0.002589 s |  264.708 s |
| Database size after initialization and maintenance |   8.008 GB |  15.195 GB |

## Results

All **11,640 measured operations** completed without errors. The tables pool
three rounds. Lower latency and higher throughput are better. FTS p95 is the
maximum of only 15 observations per backend/query; see the sampling caveat below.

### FTS5 versus PostgreSQL full-text search

| Workload                             | SQLite median / p95 (ms) | PostgreSQL median / p95 (ms) | SQLite ops/s | PostgreSQL ops/s |
| ------------------------------------ | -----------------------: | ---------------------------: | -----------: | ---------------: |
| Common: `discussion` (~25% match)    |  19,220.321 / 21,491.441 |      22,335.698 / 24,793.862 |        0.050 |            0.044 |
| Medium: `deployment` (~1.09%)        |    1,292.016 / 1,334.494 |            201.237 / 212.263 |        0.896 |              4.9 |
| Rare: `quasar` (~0.01%)              |            6.045 / 6.504 |              22.672 / 23.708 |        162.7 |             44.3 |
| Prefix: `deplo` (~1.09%)             |    1,293.404 / 1,304.671 |            201.635 / 203.410 |        0.898 |              5.0 |
| AND: `deployment rollback` (~0.099%) |          59.042 / 59.787 |              36.978 / 38.430 |         16.9 |             27.0 |
| `deployment` in channel 042          |        127.693 / 130.478 |             35.095 / 427.356 |          7.8 |             10.9 |
| Missing: `absentlexemezzz`           |            0.314 / 0.488 |              22.065 / 23.419 |      3,076.1 |             45.4 |
| `quasar`, offset 100                 |            6.302 / 7.276 |              22.605 / 24.119 |        157.6 |             44.4 |


### History and writes

| Workload                             | SQLite median / p95 (ms) | PostgreSQL median / p95 (ms) | SQLite ops/s | PostgreSQL ops/s |
| ------------------------------------ | -----------------------: | ---------------------------: | -----------: | ---------------: |
| Latest 100 messages                  |            0.965 / 4.304 |                1.561 / 2.171 |        583.7 |            613.7 |
| 100 messages halfway through history |          20.268 / 36.208 |             65.703 / 128.343 |         48.7 |             13.1 |
| Latest 100, eight concurrent callers |            7.814 / 9.170 |              11.934 / 13.005 |      1,007.4 |            665.3 |
| Insert one message                   |            0.520 / 2.503 |               9.327 / 10.075 |        699.0 |            114.9 |
| Insert, eight concurrent callers     |           4.612 / 44.283 |              74.908 / 87.154 |        712.5 |            109.2 |