informix-db/tests/benchmarks/test_select_perf.py
Ryan Malloy 90ce035a00 Phase 21: Performance benchmarks (2026.05.04.5)
Adds tests/benchmarks/ with pytest-benchmark coverage of the hot codec
paths and end-to-end SELECT/INSERT/pool/async round-trips. Establishes
a committed baseline.json so PRs can be regression-checked at review
via --benchmark-compare.

* test_codec_perf.py (16): decode/encode_param/parse_tuple_payload
  micro-benchmarks - run without container, suitable for pre-merge CI.
* test_select_perf.py (4): SELECT round-trips - 1-row latency floor,
  10-row, 1k-row full fetch, parameterized.
* test_insert_perf.py (3): single-row INSERT, executemany 100 / 1000.
* test_pool_perf.py (3): cold connect, pool acquire/release, pool
  acquire + query + release.
* test_async_perf.py (2): async round-trip overhead, 10x concurrent.
* baseline.json: committed snapshot, 28 measurements.
* benchmark pytest marker, gated off by default.
* Makefile: bench / bench-codec / bench-save targets;
  test-integration excludes benchmarks for speed.

Headline numbers (dev container loopback):
* decode(int): 181 ns
* parse_tuple 5 cols: 2.87 µs/row
* SELECT 1 round-trip: 177 µs
* Pool acquire+query+release: 295 µs
* Cold connect: 11.2 ms (72x slower than pool)

UTF-8 decode carries no measurable cost vs iso-8859-1 - confirms
Phase 20 didn't regress anything.

Total: 69 unit + 211 integration + 28 benchmark = 308 tests.
2026-05-04 17:21:12 -06:00

82 lines
2.2 KiB
Python

"""End-to-end SELECT benchmarks.
Measure the full PREPARE → EXECUTE → FETCH → CLOSE → RELEASE round-trip
for representative query shapes. The codec micro-benchmarks set the
*ceiling* (best-case CPU); these tell you how much of that ceiling
the wire protocol + server response time eats.
Layered comparison:
- ``select_one_row`` — protocol-overhead floor (single tiny round-trip)
- ``select_systables_first`` — small server-side query (~10 rows)
- ``select_bench_table_all`` — full 1k-row table fetch (sustained throughput)
"""
from __future__ import annotations
import pytest
import informix_db
pytestmark = [pytest.mark.benchmark, pytest.mark.integration]
def test_select_one_row(benchmark, bench_conn: informix_db.Connection) -> None:
"""Single-row round-trip — protocol-overhead floor."""
def run() -> object:
cur = bench_conn.cursor()
cur.execute("SELECT 1 FROM systables WHERE tabid = 1")
row = cur.fetchone()
cur.close()
return row
benchmark(run)
def test_select_systables_first_10(benchmark, bench_conn: informix_db.Connection) -> None:
"""Small server-side query — describes 4 columns, returns ~10 rows."""
def run() -> list:
cur = bench_conn.cursor()
cur.execute(
"SELECT FIRST 10 tabname, owner, tabid, ncols FROM systables"
)
rows = cur.fetchall()
cur.close()
return rows
benchmark(run)
def test_select_bench_table_all(
benchmark, bench_conn: informix_db.Connection, bench_table: str
) -> None:
"""1000-row sustained fetch — covers the typical reporting query."""
def run() -> list:
cur = bench_conn.cursor()
cur.execute(f"SELECT * FROM {bench_table}")
rows = cur.fetchall()
cur.close()
return rows
benchmark(run)
def test_select_with_param(
benchmark, bench_conn: informix_db.Connection, bench_table: str
) -> None:
"""Parameterized SELECT — exercises the BIND path."""
def run() -> list:
cur = bench_conn.cursor()
cur.execute(
f"SELECT id, name FROM {bench_table} WHERE counter > ?",
(5000,),
)
rows = cur.fetchall()
cur.close()
return rows
benchmark(run)