This commit adds an alternate implementation for `labels.Labels`, behind
a build tag `stringlabels`.
Instead of storing label names and values as individual strings, they
are all concatenated into one string in this format:
[len][name0][len][value0][len][name1][len][value1]...
The lengths are varint encoded so usually a single byte.
The previous `[]string` had 24 bytes of overhead for the slice and 16
for each label name and value; this one has 16 bytes overhead plus 1
for each name and value.
In `ScratchBuilder.Overwrite` and `Labels.Hash` we use an unsafe
conversion from string to byte slice. `Overwrite` is explicitly unsafe,
but for `Hash` this is a pure performance hack.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
`safeChunk` is only obtained from the `headChunkReader.Chunk` call where
the chunk is already fetched and stored with the `safeChunk`. So, when
getting the iterator for the `safeChunk`, we don't need to get the chunk again.
Also removed a couple of unnecessary fields from `safeChunk` as a part of this.
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
Parsing errors in the Prometheus HTTP format parser are very hard to
investigate since they only approximately indicate what is going wrong
in the parser and don't provide any information about the incorrect
input. As such it is very hard to tell what is wrong in the format
exposed by the application.
Signed-off-by: Damien Grisonnet <dgrisonn@redhat.com>
Rather than removing the previous implementation of SanitizeLabelName,
offer another version named SanitizeFullLabelName that achieved the
desired requirements, without breaking existing Prometheus code.
Update testing to validate correctness of new variant.
Signed-off-by: Nick Moore <nicholas.moore@grafana.com>
SanitizeLabelName was not correctly sanitizing label names that:
1. Started with a digit (0-9)
2. Were empty
This commit changes the santization code to catch both of these edge
cases and adds new tests to validate it works correctly in them both. In
the first case, a leading digit will be replaced with an underscore, and
in the latter, the function will return a single underscore.
Signed-off-by: Nick Moore <nicholas.moore@grafana.com>
As far as I understand it, we'd never expect to receive a nil span,
and remote.spansProtoToSpans would panic if we received a nil span.
Marking the fields as non-nullable also means the generated Golang
code doesn't use pointers for these fields, reducing allocations.
Signed-off-by: Charles Korn <charles.korn@grafana.com>
* Export single ith test histogram generation functions
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
* Do not set counter reset hint for non-gauge histograms individually
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
* Apply suggestions from code review
Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>
Signed-off-by: George Krajcsovits <krajorama@users.noreply.github.com>
---------
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Signed-off-by: George Krajcsovits <krajorama@users.noreply.github.com>
Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Correct statement in docs about query results returning either floats or histograms but not both.
* Move documentation for range and instant vectors under their corresponding headings.
Signed-off-by: Charles Korn <charles.korn@grafana.com>
