1d01435d4d
Idiomatic semaphore usage in Go, unless it is wrapping a concrete type,
should use anonymous empty structs (``struct{}``). This has several
features that are worthwhile:
1. It conveys that the object in the channel is likely used for
resource limiting / semaphore use. This is by idiom.
2. Due to magic under the hood, empty structs have a width of zero,
meaning they consume little space. It is presumed that slices,
channels, and other values of them can be represented specially
with alternative optimizations. Dmitry Vyukov has done
investigations into improvements that can be made to the channel
design and Go and concludes that there are already nice short
circuiting behaviors at work with this type.
This is the first change of several that apply this type of change to
suitable places.
In this one change, we fix a bug in the previous revision, whereby a
semaphore can be acquired for curation and never released back for
subsequent work: http://goo.gl/70Y2qK. Compare that versus the
compaction definition above.
On top of that, the use of the semaphore in the mode better supports
system shutdown idioms through the closing of channels.
Change-Id: Idb4fca310f26b73c9ec690bbdd4136180d14c32d
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| .build | ||
| coding/indexable | ||
| config | ||
| documentation | ||
| 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 | ||
| VERSION | ||
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