# dianping/cat

CAT 作为服务端项目基础组件，提供了 Java, C/C++, Node.js, Python, Go 等多语言客户端，已经在美团点评的基础架构中间件框架（MVC框架，RPC框架，数据库框架，缓存框架等，消息队列，配置系统等）深度集成，为美团点评各业务线提供系统丰富的性能指标、健康状况、实时告警等。

Repository: https://github.com/dianping/cat
Canonical: https://ross.abutalabs.com/products/cat
Language: Java
License: Apache-2.0
License Family: permissive
Topics: apm, java, distributed, realtime, monitoring, tracing, metrics
Last push: 2025-01-04T10:23:47+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:39:23.370411+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 5020, "days_push": 606, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 18944, forks 5405 (observed 2026-08-28T04:11:27.261662+00:00)

## What it is
CAT is a real-time application monitoring (APM) platform developed in Java at Meituan-Dianping, providing performance metrics, health status, and real-time alerting. It offers multi-language clients (Java, C/C++, Node.js, Python, Go) and deep integration with middleware frameworks.

## Use cases
- monitor distributed java applications in real time
- distributed tracing across microservices
- real-time alerting on application metrics
- application performance monitoring apm
- collect and visualize system health metrics
- trace slow rpc and database calls

## When to choose
- you need minute-level real-time monitoring with high throughput
- you run java-centric microservices and want deep middleware integration
- you want self-hosted apm with multi-language clients

## When to avoid
- you prefer managed cloud apm solutions
- your stack is not java-centric and community clients lack support
- you need modern opentelemetry ecosystem compatibility

## Facets
- artifact type: service
- maturity: active
- function: monitoring, tracing, alerting
- domain: monitoring, microservices
- platform: jvm, self-hosted, cross-platform
- tags: apm, application-monitoring, metrics, realtime, devops

## Member repositories
- dianping/cat (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:27.261662+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:01:00.245822+00:00, confidence not recorded.
  - readme: https://github.com/dianping/cat (fetched 2026-08-28T04:11:27.261662+00:00, sha d347854a930e)
- Data as of 2026-08-30T08:39:29.467469+00:00.