61d26e8445
Prometheus needs long-term storage. Since we don't have enough resources to build our own timeseries storage from scratch ontop of Riak, Cassandra or a similar distributed datastore at the moment, we're planning on using OpenTSDB as long-term storage for Prometheus. It's data model is roughly compatible with that of Prometheus, with some caveats. As a first step, this adds write-only replication from Prometheus to OpenTSDB, with the following things worth noting: 1) I tried to keep the integration lightweight, meaning that anything related to OpenTSDB is isolated to its own package and only main knows about it (essentially it tees all samples to both the existing storage and TSDB). It's not touching the existing TieredStorage at all to avoid more complexity in that area. This might change in the future, especially if we decide to implement a read path for OpenTSDB through Prometheus as well. 2) Backpressure while sending to OpenTSDB is handled by simply dropping samples on the floor when the in-memory queue of samples destined for OpenTSDB runs full. Prometheus also only attempts to send samples once, rather than implementing a complex retry algorithm. Thus, replication to OpenTSDB is best-effort for now. If needed, this may be extended in the future. 3) Samples are sent in batches of limited size to OpenTSDB. The optimal batch size, timeout parameters, etc. may need to be adjusted in the future. 4) OpenTSDB has different rules for legal characters in tag (label) values. While Prometheus allows any characters in label values, OpenTSDB limits them to a to z, A to Z, 0 to 9, -, _, . and /. Currently any illegal characters in Prometheus label values are simply replaced by an underscore. Especially when integrating OpenTSDB with the read path in Prometheus, we'll need to reconsider this: either we'll need to introduce the same limitations for Prometheus labels or escape/encode illegal characters in OpenTSDB in such a way that they are fully decodable again when reading through Prometheus, so that corresponding timeseries in both systems match in their labelsets. Change-Id: I8394c9c55dbac3946a0fa497f566d5e6e2d600b5 |
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| .build | ||
| coding | ||
| config | ||
| documentation/examples | ||
| model | ||
| notification | ||
| retrieval | ||
| rules | ||
| stats | ||
| storage | ||
| tools | ||
| utility | ||
| web | ||
| .gitignore | ||
| .pkgignore | ||
| .travis.yml | ||
| build_info.go | ||
| CONTRIBUTING.md | ||
| CONTRIBUTORS.md | ||
| Dockerfile | ||
| LICENSE | ||
| main.go | ||
| Makefile | ||
| Makefile.INCLUDE | ||
| MANIFEST | ||
| README.md | ||
| tests-for-die-in-a-fire-travis.sh | ||
Prometheus
Bedecke deinen Himmel, Zeus! A new kid is in town.
Prometheus is a generic time series collection and computation server that is useful in the following fields:
- Industrial Experimentation / Real-Time Behavioral Validation / Software Release Qualification
- Econometric and Natural Sciences
- Operational Concerns and Monitoring
The system is designed to collect telemetry from named targets on given intervals, evaluate rule expressions, display the results, and trigger an action if some condition is observed to be true.
Prerequisites
If you read below in the Getting Started section, the build infrastructure will take care of the following things for you in most cases:
- Go 1.1.
- LevelDB: https://code.google.com/p/leveldb/.
- Protocol Buffers Compiler: http://code.google.com/p/protobuf/.
- goprotobuf: the code generator and runtime library: http://code.google.com/p/goprotobuf/.
- Levigo, a Go-wrapper around LevelDB's C library: https://github.com/jmhodges/levigo.
- GoRest, a RESTful style web-services framework: http://code.google.com/p/gorest/.
- Prometheus Client, Prometheus in Prometheus https://github.com/prometheus/client_golang.
- Snappy, a compression library for LevelDB and Levigo http://code.google.com/p/snappy/.
Getting Started
For basic help how to get started:
- The source code is periodically indexed: Prometheus Core.
- For UNIX-like environment users, please consult the Travis CI configuration in .travis.yml and Makefile.
- All of the core developers are accessible via the Prometheus Developers Mailinglist.
General
For first time users, simply run the following:
$ make
$ ARGUMENTS="-configFile=documentation/examples/prometheus.conf" make run
${ARGUMENTS} is passed verbatim into the makefile and thusly Prometheus as
$(ARGUMENTS). This is useful for quick one-off invocations and smoke
testing.
If you run into problems, try the following:
$ SILENCE_THIRD_PARTY_BUILDS=false make
Upon having a satisfactory build, it's possible to create an artifact for end-user distribution:
$ make package
$ find build/package
build/package will be sufficient for whatever archiving mechanism you
choose. The important thing to note is that Go presently does not
staticly link against C dependency libraries, so including the lib
directory is paramount. Providing LD_LIBRARY_PATH or
DYLD_LIBRARY_PATH in a scaffolding shell script is advised.
Problems
If at any point you run into an error with the make build system in terms of
its not properly scaffolding things on a given environment, please file a bug or
open a pull request with your changes if you can fix it yourself.
Please note that we're explicitly shooting for stable runtime environments and not the latest-whiz bang releases; thusly, we ask you to provide ample architecture and release identification remarks for us.
Testing
$ make test
Packaging
$ make package
Race Detector
Go 1.1 includes a race detector which can be enabled at build time. Here's how to use it with Prometheus (assumes that you've already run a successful build).
To run the tests with race detection:
$ GORACE="log_path=/tmp/foo" go test -race ./...
To run the server with race detection:
$ go build -race .
$ GORACE="log_path=/tmp/foo" ./prometheus
Contributing
Refer to CONTRIBUTING.md
License
Apache License 2.0