discord9 b3c756a7dd perf(promql): reduce timestamp payload allocations and use narrow cursor scans (#9417)
* perf(promql): zero-copy timestamp payload for millisecond zero-offset ranges

RangeManipulate rebuilt the timestamp range payload per sample through
wide-precision i128 conversion even for millisecond input with zero
offset, where the input is already millisecond and nothing changes.
That turned a previously zero-copy path into a per-sample loop plus a
Vec allocation, regressing range-function queries.

Reuse the input timestamp array directly when the time index is already
millisecond and the offset is zero. Other units and non-zero offsets
keep the wide-precision conversion (required so ns/us data near the
native type limits stays correct under large offsets).

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
Signed-off-by: discord9 <discord9@163.com>

* perf(promql): vectorize timestamp payload with plain i64

RangeManipulate rebuilt the timestamp range payload per sample through
wide-precision i128 conversion, turning a hot path into a scalar loop
with a Vec allocation. Realistic timestamps and offsets stay far inside
i64, so the wide path is unnecessary.

- millisecond + zero offset reuses the input array with zero copy;
- other units / offsets shift in one vectorized i64 pass (no i128, no
  per-sample Option, no overflow branch).

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
Signed-off-by: discord9 <discord9@163.com>

* perf(promql): check timestamp payload overflow via arrow try_unary

Replace the silent wrapping shift with try_unary + checked_mul/checked_add.
checked arithmetic lowers to a per-lane overflow flag so the single pass
still vectorizes over the dense i64 buffer; any overflow short-circuits to
an error instead of silently wrapping to a wrong timestamp. No i128, no
per-sample Option.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
Signed-off-by: discord9 <discord9@163.com>

* perf(promql): vectorize cursor scans with i64 fast path

RangeManipulate::calculate_range and InstantManipulate::manipulate
compared every sample through i128 wide-precision arithmetic. For
realistic timestamps and offsets the shifted values stay far inside
i64, so the wide path was pure overhead.

Split both scans into an i64 fast path (checked arithmetic precomputed
once per batch) and an i128 exact fallback. Any input that would
overflow i64 falls back to the i128 scan, keeping window membership
semantics identical.

Verified: 47/47 range_manipulate + instant_manipulate tests, 275/275
promql crate tests, 1612 randomized cases byte-identical to i128 scan.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
Signed-off-by: discord9 <discord9@163.com>

* refactor(promql): generalize cursor scans and share endpoint precheck

Address review comments on PR #9417:
- Generalize scan_ranges/scan_instants over Nanoseconds (i64/i128),
  eliminating the duplicated scan bodies.
- Extract shared narrow_scan precheck used by both RangeManipulate and
  InstantManipulate, with identical checked endpoint logic.
- Trim doc comments to one line; fix factual errors about fallback
  trigger (2262 for ms/s, not native type limits).

Semantics unchanged: same cursor algorithm, same overflow fallback,
same i64-vs-i128 selection, same stale/null/tie handling.

Verified: 47/47 range_manipulate + instant_manipulate tests, clippy clean.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
Signed-off-by: discord9 <discord9@163.com>

* perf(promql): vectorize payload with try_unary and add scan carrier bench

Replace the per-sample i128 payload loop with a single arrow try_unary
pass: i128 intermediate holds any native timestamp shift, only the final
millisecond result must fit i64. This is semantically equivalent to the
original i128 implementation (no silent wrap, no per-sample branching).

Add cursor_scan_carriers A/B benchmark: i64 fast path vs i128 exact
fallback on four workloads. Add five deterministic differential tests
pinning scan_ranges::<i64> and scan_ranges::<i128> to be pointwise
equivalent on boundary shapes (sub-ms samples, fallback triggers,
nanosecond extremes, seeded precision matrix).

Bench (N=4096, 15s cadence):
- payload wall_time 20x15s: 74.94us -> 48.98us (-35%)
- payload wall_time 240x15s: 102.44us
- scan i64 fast path: 10.97us vs i128 19.84us (1.81x)

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* perf(promql): restore zero-copy payload for ms+offset=0 and fix comment

Restore the zero-copy fast path for millisecond timestamps with zero
offset, guarded by the input column's exact data type (Timestamp
(Millisecond, None)) rather than self.time_unit. The old time_unit guard
would accept a tz-carrying millisecond column and produce a dictionary
value type disagreeing with the output schema; the datatype guard is the
correct check.

Also fix the comment: arrow's try_unary is a fallible kernel that LLVM
cannot auto-vectorize; the win over the hand-written loop comes from
eliminating the per-sample Option/Vec and branches, not SIMD.

Add a regression test with a timezone-carrying millisecond index to
prove it falls back to the try_unary path.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* perf(promql): replace try_unary with unary + Cell overflow flag

Arrow's try_unary is a fallible kernel that LLVM cannot auto-vectorize.
Replace it with the infallible unary kernel: the closure is a plain
i64 -> i64 mapping that sets a Cell<bool> on overflow instead of
returning Err per sample. The flag is checked once after the loop.

This removes the per-lane Result construction and lets LLVM vectorize
the shift+truncate sequence. Bench (N=4096, 15s cadence):
- window4x15s: 42.12us -> 28.77us (-32%)
- window20x15s: 48.98us -> 27.68us (-43%)
- window240x15s: 102.44us -> 27.61us (-73%)
- regular_sparse: 90.04us -> 29.20us (-68%)

All cases now run at ~27-29us regardless of window size; the zero-copy
path dominates for ms+offset=0.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* perf(promql): dispatch payload conversion on null_count; drop wall-time bench

Null-free batches (dominant PromQL case) take arrow's vectorizable unary
kernel with a Cell<bool> overflow flag; nullable batches take try_unary so
a NULL slot's arbitrary underlying value cannot raise a false batch-wide
overflow error. Add a regression test exercising both paths.

Remove bench_range_manipulate_wall_time (all-ms zero-offset cases only
exercised the zero-copy path, measuring nothing about the conversion) and
its orphaned helpers; restore the cursor-scan bench helpers it shared.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

* fix(promql): keep nullable timestamp cursor scans on i128

NULL slots may contain unordered arbitrary values, so the endpoint-only
narrow-scan proof cannot bound their interior timestamp arithmetic. Both
range and instant scans now attempt i64 only for null-free timestamp arrays
and otherwise retain the existing exact i128 path.

Add focused interior-NULL regressions through both active entrypoints,
checking concrete selections and output against the existing wide scan.
The null-free fast path and timestamp payload conversion are unchanged.

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>

---------

Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
Signed-off-by: discord9 <discord9@163.com>
2026-10-09 10:45:15 +00:00
2023-08-10 08:08:37 +00:00
2023-06-25 11:05:46 +08:00
2023-11-09 10:38:12 +00:00

GreptimeDB Logo

Metrics, logs, and traces.
One engine, on your infrastructure.

A columnar database for metrics, logs, and traces on object storage. Apache-2.0 licensed core.

User Guide  ·  API Docs  ·  Roadmap 2026  ·  Slack

Stable Canary Nightly Docker Pulls License

stable for production  ·  canary includes pre-releases  ·  nightly is a weekly snapshot of main

Introduction

GreptimeDB is an open-source observability database. Metrics, logs, and traces run on one columnar engine over object storage and share one table model: tags, timestamp, and fields. When signals carry common identifiers such as service, host, or trace ID, you can correlate them in SQL without moving data between databases.

Ingest through OpenTelemetry, Prometheus Remote Write, Loki Push, or Elasticsearch Bulk. Use SQL across observability data and PromQL for metrics. Migrate ingestion one signal at a time without rebuilding your collectors.

One Query Across Signals

OpenTelemetry ingestion writes spans to opentelemetry_traces and log records to opentelemetry_logs. Both tables carry trace_id, so correlating them is a join:

-- The slowest failed spans in the last hour,
-- with the log lines emitted inside those same traces.
SELECT
    t.service_name,
    t.span_name,
    t.duration_nano / 1000000 AS duration_ms,
    l.timestamp AS log_time,
    l.severity_text,
    l.body
FROM opentelemetry_traces t
JOIN opentelemetry_logs l ON l.trace_id = t.trace_id
WHERE t.timestamp > now() - INTERVAL '1' HOUR
  AND t.span_status_code = 'STATUS_CODE_ERROR'
ORDER BY t.duration_nano DESC
LIMIT 20;

Metrics join the same way, on any tag the tables share, such as service, host, or pod.

Why You Might Use It

  • You run Prometheus plus Loki or Elasticsearch and want one backend instead of three
  • You have outgrown Prometheus on cardinality or retention and don't want the Thanos/Mimir operational surface
  • You are hitting Loki's query performance limits as log volume grows
  • You need long retention on object storage without a separate analytics stack
  • You want to query telemetry with SQL, not only a domain query language
  • You are storing GenAI or agent telemetry (OTel GenAI conventions) alongside infrastructure signals

Learn more in Why GreptimeDB.

What's Supported

Ingest OpenTelemetry (OTLP), Prometheus Remote Write, Loki Push, Elasticsearch Bulk, InfluxDB line protocol, gRPC
Query SQL, PromQL, Jaeger-compatible trace queries, MySQL and PostgreSQL wire protocols
Storage S3, GCS, Azure Blob and S3-compatible endpoints as primary storage, with memory and local-disk caches
Built in Retention policies, downsampling, continuous aggregation, explicit table partitioning, and inverted / skipping / fulltext indexes

Compute and storage are disaggregated: object storage holds the data, while memory and local-disk caches keep recent and frequently queried data close to compute.

GreptimeDB Overview

Benchmarks

Compatibility and Migration

Compatibility is per protocol, and query-side coverage is narrower than ingestion.

Compatible Not compatible
Prometheus Remote Write ingestion; PromQL queries Gaps are listed in PromQL compatibility
Loki Push ingestion; dual-write through Grafana Alloy makes the cutover gradual LogQL and the rest of the Loki query API
Elasticsearch _bulk ingestion in the open-source core; QueryDSL partially, in Enterprise Most other Elasticsearch APIs

Limitations and Edition Boundary

Cluster deployment, object storage, the Flow engine, and every ingestion protocol listed above are in the Apache-2.0 build. Repartitioning, region migration, and index creation are manual operations there.

Read replicas, workload isolation, and automated repartitioning are GreptimeDB Enterprise features, along with enterprise security and governance. The Enterprise overview has the current list, and pricing has the edition comparison.

Architecture

GreptimeDB can run in two modes:

  • Standalone — single binary for development and small deployments.
  • Distributed — four components, each independently scalable:
    • Frontend — protocol entry (OTel, Prometheus, MySQL/PostgreSQL, gRPC, ingestion APIs for Elasticsearch/InfluxDB/Loki) and the distributed query engine. Stateless, scales horizontally.
    • Datanode — region engine with WAL, memtable, SST, cache, compaction, and indexes. Persists data to object storage. Elastic.
    • Metasrv — metadata, routing, repartitioning, and security. Backed by a pluggable KV layer (etcd or RDS).
    • Flownode (optional) — continuous flow computation (streaming and materialized views).

For deeper coverage, see the architecture doc or DeepWiki.

GreptimeDB System Overview

Try GreptimeDB

For AI agents — paste this prompt into your agent:

Read https://docs.greptime.com/SKILL.md and follow the instructions
to deploy, configure, ingest, and query GreptimeDB.
docker run -p 127.0.0.1:4000-4003:4000-4003 \
  -v "$(pwd)/greptimedb_data:/greptimedb_data" \
  --name greptime --rm \
  greptime/greptimedb:latest standalone start \
  --http-addr 0.0.0.0:4000 \
  --grpc-bind-addr 0.0.0.0:4001 \
  --mysql-addr 0.0.0.0:4002 \
  --postgres-addr 0.0.0.0:4003

Dashboard: http://localhost:4000/dashboard

Read more in the full Install Guide.

Troubleshooting:

  • Cannot connect to the database? Ensure that ports 4000, 4001, 4002, and 4003 are not blocked by a firewall or used by other services.
  • Failed to start? Check the container logs with docker logs greptime for further details.

Getting Started

Build From Source

Prerequisites:

  • Rust toolchain — stable, pinned by rust-toolchain.toml
  • Protobuf compiler (>= 3.15)
  • C/C++ building essentials: gcc / g++ / autoconf and the glibc dev package (libc6-dev on Ubuntu, glibc-devel on Fedora)
  • Python toolchain (optional, only for some test scripts)

Build and run:

make                          # build greptime binary
cargo run -- standalone start # start in standalone mode

Common dev commands:

make fmt            # format Rust code
make clippy         # lint (fails on warnings)
make test           # unit + integration tests (uses cargo-nextest)
make sqlness-test   # SQL regression tests

See the Contribution Guidelines for the full developer workflow.

Tools & Extensions

Project Status

GreptimeDB is generally available, with stable APIs and regular releases. It runs in production at scale — OceanBase Cloud operates 80+ GreptimeDB clusters managing 300 TB of logs, cutting log storage cost by 60%+ after migrating from Grafana Loki. See more in case studies.

Release lines and support windows are in the version reference. For where the project is going, read the v1.0 highlights and the 2026 roadmap.

Community

We invite you to engage and contribute!

If GreptimeDB is useful to you, please star the repo.

Known Users

License

GreptimeDB is an open-core project. Its core is licensed under the Apache License 2.0.

A small set of peripheral, enterprise-only features are gated behind the enterprise Cargo feature (not built by default) and are governed by the separate GreptimeDB Enterprise License. Source files under that license carry an explicit Enterprise License header.

Commercial Support

Scaling observability on your infrastructure? GreptimeDB Enterprise adds the operational, security, and support layer for production deployments. Contact us for details.

Contributing

Integration CI Codecov

Acknowledgement

Special thanks to all contributors! See AUTHOR.md.


All trademarks, logos, and brand names referenced in this README and in the Overview diagram are the property of their respective owners. Their use is for identification purposes only and does not imply endorsement or affiliation.

S
Description
Open-source, cloud-native, unified observability database for metrics, logs and traces, supporting SQL/PromQL/Streaming.
Readme Apache-2.0
1.4 GiB
Languages
Rust 98%
Python 1.3%
Shell 0.3%
JavaScript 0.2%