These are all simple changes we should have caught a long time ago:
1. The hashing mechanism for fingerprint label sets should have not
allocated new objects for the actual hashing---at least not
egregiously. This simplifies the hash writing by just byte-
dumping the string stream into the hasher.
2. The hashing mechanism within the scope of a metric does not care
about the value of the label keys themselves but only of the label
values. The keys can be dropped from the calculation.
3. The locking mechanism for the metrics should not block on hash
computation but rather solely on the actual mutation or critical
section reads.
4. For scalar metrics (i.e., ones with niladic label signatures), we
should rely on a preallocated map versus requesting a new one
ad hoc.
This is tested with Go 1.1, so the results may yield other values
for us elsewhere:
BEFORE
BenchmarkLabelValuesToSignatureScalar 500000000 3.97 ns/op 0 B/op 0 allocs/op
BenchmarkLabelValuesToSignatureSingle 5000000 714 ns/op 74 B/op 4 allocs/op
BenchmarkLabelValuesToSignatureDouble 1000000 1153 ns/op 107 B/op 5 allocs/op
BenchmarkLabelValuesToSignatureTriple 1000000 1588 ns/op 138 B/op 6 allocs/op
BenchmarkLabelToSignatureScalar 500000000 3.91 ns/op 0 B/op 0 allocs/op
BenchmarkLabelToSignatureSingle 2000000 874 ns/op 92 B/op 5 allocs/op
BenchmarkLabelToSignatureDouble 1000000 1528 ns/op 139 B/op 7 allocs/op
BenchmarkLabelToSignatureTriple 1000000 2172 ns/op 186 B/op 9 allocs/op
AFTER
BenchmarkLabelValuesToSignatureScalar 500000000 4.36 ns/op 0 B/op 0 allocs/op
BenchmarkLabelValuesToSignatureSingle 5000000 378 ns/op 89 B/op 4 allocs/op
BenchmarkLabelValuesToSignatureDouble 5000000 574 ns/op 142 B/op 5 allocs/op
BenchmarkLabelValuesToSignatureTriple 5000000 758 ns/op 186 B/op 6 allocs/op
BenchmarkLabelToSignatureScalar 500000000 4.06 ns/op 0 B/op 0 allocs/op
BenchmarkLabelToSignatureSingle 5000000 472 ns/op 106 B/op 5 allocs/op
BenchmarkLabelToSignatureDouble 2000000 746 ns/op 174 B/op 7 allocs/op
BenchmarkLabelToSignatureTriple 1000000 1061 ns/op 235 B/op 9 allocs/op
In effect, a single metric mutation operation's lookup overhead will
move from Before::iBenchmarkLabelToSignature to
After::BenchmarkLabelValuesToSignature. This MINIMALLY reduces
1/2 the overhead. I would be hesitant in reading the memory
allocation statistics, for this was run with the GC still on and
thusly inaccurate per Go benchmarking documentation.
Before::BenchmarkLabelValuesToSignature never existed, so it is not
of any intrinsic value in itself. That said, the cases that still
rely on LabelToSignature experience consistently a 1/2 drop in time.
Change-Id: Ifc9e69f718af65a59f5be8117473518233258159
This hook is needed for the upcoming push gateway.
Also remove go vet warnings and add test for Handler().
Change-Id: If6c56676c7a0f10c16b4effae7285903f8267616
This also adds a check that forbids any user-supplied metrics to start
with the reserved label name prefix "__".
Change-Id: I2fe94c740b685ad05c4c670613cf2af7b9e1c1c0
This is an optimization of labelsToSignature to avoid excess allocations
when the label set is empty.
Change-Id: If2d59bbc3ae6d4457e2ded197b6f4e7c67e6a173
This ensures that you can pass the same base label set into multiple
Register() calls, e.g.:
labels := map[string]string{"key": "value"}
prometheus.Register("metric_1", "", labels, ...)
prometheus.Register("metric_2", "", labels, ...)
Change-Id: I951e5c2ed7844c74eb3716d1bf07126ce558f266
This commit introduces all relevant server-side artifacts such that the
Result streams can be used by external parties for one-off tools and
such. This will ultimately better enable us to support additional
wireformats with much more ease.
Bernerd had suggested extracting the value decoders and bundling them
into the client library. After some reflection, I tend to agree with
this, since we can start breaking the onion of Prometheus itself and
localize the protocol management into its own scope.
A couple of major changes since moving:
- Protocol 0.0.2 has moved to a struct{} so that our tests can perform
value matching, which cannot be done against function literals.
- Processing now acquires options to dictate behavioral changes of
metrics bodies.
- Processing no longer closes the stream, thusly returning this to the
hands of the caller.
- Process() has been renamed to ProcessSingle to better convey that it
works on complete message bodies. This paves the way for better
streaming payload support that the next API version will offer.
* Drop `AsMarshallable()` from the Metric interface. Use
`json.Marshaler` and `MarshalJSON()`, and leverage JSON struct tags
where possible.
* Add `MarshalJSON()` to Registry and remove `dumpToWriter`, which
makes the registry handler much simpler.
In addition to simplifying some of the marshalling behavior, this also
has the nice side effect of cutting down the number of
`map[string]interface{}` instances.