mz-benchmark
Testing & QualityAdd/modify/debug Materialize perf benchmark scenarios. Three frameworks: Feature Benchmark (single-op micro), Scalability Test (SQL throughput under concurrency), Parallel Benchmark (sustained latency via scenarios.py). Trigger: "benchmark", "feature benchmark", "scalability test", "parallel benchmark", "performance regression", "micro-benchmark", "TPS", "latency test", or edits in feature_benchmark/scenarios/, scalability/workload/workloads/, parallel_benchmark/scenarios.py. Note: measurement, not panic-stress (see mz-parallel-workload).
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Benchmark Frameworks
Materialize has some benchmark frameworks targetting local Docker, each suited to different performance concerns. Choose the right one based on what you're measuring.
Decision Guide
| Concern | Framework | Best For |
|---|---|---|
| Single-operation latency | Feature Benchmark | "How fast is this SELECT / INSERT / CREATE INDEX?" |
| SQL throughput under concurrency | Scalability Test | "How many QPS can we sustain at 1/4/16/64/256 concurrent clients?" |
| Sustained performance over time | Parallel Benchmark | "Does latency degrade over a 2-minute mixed workload?" |
1. Feature Benchmark (Micro-benchmarks)
Measures wall-clock time of individual SQL operations without concurrency. Uses testdrive fragments. Great for regression-testing specific code paths.
How to Add a Scenario
- Add a class in one of the
scenarios/*.pyfiles. ExtendScenario(default, runs in CI),ScenarioBig(longer, opt-in), orScenarioDisabled. - Implement
benchmark()returning aTd(...)with timing markers (/* A */and/* B */). - Optionally implement
shared(),init(),before()if setup is required.
Scenario Template
from materialize.feature_benchmark.action import TdAction
from materialize.feature_benchmark.measurement_source import MeasurementSource, Td
from materialize.feature_benchmark.scenario import Scenario
class MyCategory(Scenario):
"""Group parent - won't run (not a leaf)."""
pass
class MySpecificBenchmark(MyCategory):
"""Leaf class - this runs."""
def init(self) -> list[TdAction]:
return [
self.table_ten(), # Creates table 'ten' with values 0-9
TdAction("""
> CREATE TABLE t1 (f1 INTEGER);
> INSERT INTO t1 SELECT {unique_values} FROM {join};
> SELECT COUNT(*) FROM t1;
{n}
""".format(
unique_values=self.unique_values(),
join=self.join(),
n=self.n(),
)),
]
def benchmark(self) -> MeasurementSource:
return Td("""
> SELECT 1;
/* A */
1
> SELECT COUNT(*) FROM t1 WHERE f1 % 2 = 0;
/* B */
{half_n}
""".format(half_n=self.n() // 2))
Timing Markers
/* A */- Start marker. Measurement begins AFTER this completes./* B */- End marker. Measurement ends when this completes.- Measures: time from end of A to end of B.
- For a single query, use
SELECT 1; /* A */as a dummy start to not measure the overhead of Testdrive starting up.
Scenario Phases (execution order)
shared()- Runs once for BOTH instances (e.g., create Kafka topics)init()- Runs once per instance (create tables, populate data)before()- Runs before EACH iteration (restart, cleanup)benchmark()- Runs repeatedly (10-50 times), measured
Helpers
self.n()- Returns 10^SCALE (default SCALE=6 → 1,000,000)self.table_ten()/self.view_ten()- Creates table/view with values 0-9self.unique_values()- SQL expression generating N unique values via cartesian productself.join()- SQL FROM clause for cartesian product joinsself.keyschema()/self.schema()- Kafka schema helpers
Tips
- Aim for ~1 second query time. Too fast = noise; too slow = Unbearably slow CI.
- Test td fragments locally with standalone testdrive before running the full benchmark.
- Use
SCALEto control data volume:SCALE = 5→ 100K rows. - Use
FIXED_SCALE = Trueif--scaleshould not affect your scenario. This is usually done when a scenario doesn't scale well, add an explanation. - Use
RELATIVE_THRESHOLDto customize regression sensitivity per scenario.
Running
bin/mzcompose --find feature-benchmark run default --root-scenario=MyCategory
bin/mzcompose --find feature-benchmark run default --root-scenario=MySpecificBenchmark
2. Scalability Test (SQL Throughput Under Concurrency)
Measures TPS (transactions per second) at increasing concurrency levels (1, 2, 4, 8, ..., 256 clients). Open-loop benchmark that identifies scaling bottlenecks. Compares Materialize against Postgres.
How to Add a Workload
- Create a new file or add to an existing file in
workload/workloads/. - Extend a marker class (
DmlDqlWorkload,DdlWorkload, orConnectionWorkload). - Implement
operations()returning a list ofOperationobjects.
Workload Template (Simple DML/DQL)
from materialize.scalability.operation.operations.operations import (
SelectOne,
InsertDefaultValues,
SelectCountInMv,
)
from materialize.scalability.workload.workload_markers import DmlDqlWorkload
class MyWorkload(DmlDqlWorkload):
def operations(self) -> list["Operation"]:
return [InsertDefaultValues(), SelectCountInMv()]
Workload Template (DDL with Data Exchange)
from materialize.scalability.operation.operation_data import OperationData
from materialize.scalability.operation.operations.operations import (
CreateTableX, PopulateTableX, SelectStarFromTableX, DropTableX,
)
from materialize.scalability.operation.scalability_operation import OperationChainWithDataExchange
from materialize.scalability.workload.workload import WorkloadWithContext
from materialize.scalability.workload.workload_markers import DdlWorkload
class MyDdlWorkload(WorkloadWithContext, DdlWorkload):
def amend_data_before_execution(self, data: OperationData) -> None:
data.push("table_seed", data.get("worker_id"))
def operations(self) -> list["Operation"]:
return [
OperationChainWithDataExchange([
CreateTableX(), PopulateTableX(), SelectStarFromTableX(), DropTableX(),
])
]
Custom Operations
from materialize.scalability.operation.scalability_operation import SimpleSqlOperation
class MyCustomSelect(SimpleSqlOperation):
def sql_statement(self) -> str:
return "SELECT COUNT(*) FROM t1 WHERE f1 > 500;"
Built-in Operations
SelectOne, SelectStar, SelectLimit, SelectCount, SelectCountInMv, SelectUnionAll, Update, InsertDefaultValues, CreateTableX, PopulateTableX, DropTableX, CreateMvOnTableX, DropMvOfTableX, Connect, Disconnect.
Database Schema (auto-created)
For each workload, the framework creates: CREATE TABLE t1 (f1 INTEGER DEFAULT 1), inserts a row, and creates CREATE MATERIALIZED VIEW mv1 AS SELECT count(*) AS count FROM t1.
Running
bin/mzcompose --find scalability run default --workload MyWorkload
bin/mzcompose --find scalability run default --workload-group-marker DmlDqlWorkload
bin/mzcompose --find scalability run default --min-concurrency 1 --max-concurrency 128
3. Parallel Benchmark (Sustained Performance)
Measures latency distributions (p50/p95/p99) and QPS over a sustained load period (default 120s). Supports mixed workloads with both open-loop and closed-loop concurrency. Detects latency degradation over time via slope analysis.
How to Add a Scenario
- Add a class in
scenarios.pyextendingScenario. - In
__init__, callself.init(phases=[...])withTdPhase(setup) andLoadPhase(benchmark).
Scenario Template
from materialize.parallel_benchmark.framework import (
ClosedLoop,
LoadPhase,
OpenLoop,
Periodic,
ReuseConnQuery,
Scenario,
StandaloneQuery,
TdPhase,
)
class MyScenario(Scenario):
def __init__(self, c, conn_infos):
self.init(
phases=[
# Setup phase (testdrive)
TdPhase("""
> CREATE TABLE bench_t (f1 INTEGER);
> INSERT INTO bench_t SELECT generate_series(1, 10000);
> CREATE MATERIALIZED VIEW bench_mv AS
SELECT COUNT(*) AS c FROM bench_t;
> SELECT c FROM bench_mv;
10000
"""),
# Benchmark phase
LoadPhase(
duration=120, # seconds
actions=[
OpenLoop(
action=StandaloneQuery(
"SELECT c FROM bench_mv",
conn_infos["materialized"],
),
dist=Periodic(per_second=100),
report_regressions=True,
),
ClosedLoop(
action=ReuseConnQuery(
"INSERT INTO bench_t VALUES (1)",
conn_infos["materialized"],
),
report_regressions=True,
),
],
),
],
guarantees={
"SELECT c FROM bench_mv (standalone)": {
"qps": 10,
"p99": 500,
},
},
)
Action Types
| Class | Behavior | Use When |
|---|---|---|
StandaloneQuery | New connection per operation | Testing connection overhead + query |
ReuseConnQuery | Persistent single connection | Testing pure query latency |
PooledQuery | Draws from connection pool | Testing pooled throughput (set conn_pool_size > 0) |
Load Patterns
| Class | Behavior |
|---|---|
OpenLoop(dist=Periodic(per_second=N)) | Fixed-rate: N operations/second regardless of latency |
OpenLoop(dist=Gaussian(mean, stddev)) | Variable-rate: sleep drawn from gaussian distribution |
ClosedLoop(...) | Sequential: next operation starts when previous completes |
Guarantees and Regression Thresholds
# Absolute guarantees (fail if not met)
guarantees={
"SELECT 1 (standalone)": {"qps": 15, "p99": 400, "max": 500},
}
# Relative thresholds (fail if regression vs baseline)
regression_thresholds={
"SELECT 1 (pooled)": {"qps": 0.8, "p99": 1.3}, # QPS must be >=80% of baseline
}
Action names are auto-generated as "{query} ({connection_type})".
Available Metrics
queries, qps, min, max, avg, p50, p95, p99, p99.9, ..., p99.999999, std, slope.
Disabling a Scenario
from materialize.parallel_benchmark.framework import disabled
@disabled("Reason for disabling")
class MyScenario(Scenario):
...
Running
bin/mzcompose --find parallel-benchmark run default --scenario MyScenario
bin/mzcompose --find parallel-benchmark run default --scenario MyScenario --load-phase-duration 60