prompb: Add histograms to remote write/read protobufs

Signed-off-by: beorn7 <beorn@grafana.com>
This commit is contained in:
beorn7 2022-06-15 17:20:27 +02:00
parent 095b6c93dd
commit d9d51c565c
4 changed files with 1533 additions and 72 deletions

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@ -34,8 +34,10 @@ const (
// Content-Type: "application/x-protobuf"
// Content-Encoding: "snappy"
ReadRequest_SAMPLES ReadRequest_ResponseType = 0
// Server will stream a delimited ChunkedReadResponse message that contains XOR encoded chunks for a single series.
// Each message is following varint size and fixed size bigendian uint32 for CRC32 Castagnoli checksum.
// Server will stream a delimited ChunkedReadResponse message that
// contains XOR or HISTOGRAM(!) encoded chunks for a single series.
// Each message is following varint size and fixed size bigendian
// uint32 for CRC32 Castagnoli checksum.
//
// Response headers:
// Content-Type: "application/x-streamed-protobuf; proto=prometheus.ChunkedReadResponse"

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@ -39,8 +39,10 @@ message ReadRequest {
// Content-Type: "application/x-protobuf"
// Content-Encoding: "snappy"
SAMPLES = 0;
// Server will stream a delimited ChunkedReadResponse message that contains XOR encoded chunks for a single series.
// Each message is following varint size and fixed size bigendian uint32 for CRC32 Castagnoli checksum.
// Server will stream a delimited ChunkedReadResponse message that
// contains XOR or HISTOGRAM(!) encoded chunks for a single series.
// Each message is following varint size and fixed size bigendian
// uint32 for CRC32 Castagnoli checksum.
//
// Response headers:
// Content-Type: "application/x-streamed-protobuf; proto=prometheus.ChunkedReadResponse"

File diff suppressed because it is too large Load diff

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@ -54,6 +54,65 @@ message Exemplar {
int64 timestamp = 3;
}
// A native histogram, also known as a sparse histogram.
// Original design doc:
// https://docs.google.com/document/d/1cLNv3aufPZb3fNfaJgdaRBZsInZKKIHo9E6HinJVbpM/edit
// The appendix of this design doc also explains the concept of float
// histograms. This Histogram message can represent both, the usual
// integer histogram as well as a float histogram.
message Histogram {
enum ResetHint {
UNKNOWN = 0; // Need to test for a counter reset explicitly.
YES = 1; // This is the 1st histogram after a counter reset.
NO = 2; // There was no counter reset between this and the previous Histogram.
GAUGE = 3; // This is a gauge histogram where counter resets don't happen.
}
oneof count { // Count of observations in the histogram.
uint64 count_int = 1;
double count_float = 2;
}
double sum = 3; // Sum of observations in the histogram.
// The schema defines the bucket schema. Currently, valid numbers
// are -4 <= n <= 8. They are all for base-2 bucket schemas, where 1
// is a bucket boundary in each case, and then each power of two is
// divided into 2^n logarithmic buckets. Or in other words, each
// bucket boundary is the previous boundary times 2^(2^-n). In the
// future, more bucket schemas may be added using numbers < -4 or >
// 8.
sint32 schema = 4;
double zero_threshold = 5; // Breadth of the zero bucket.
oneof zero_count { // Count in zero bucket.
uint64 zero_count_int = 6;
double zero_count_float = 7;
}
Buckets negative_buckets = 8;
Buckets positive_buckets = 9;
ResetHint reset_hint = 10;
// timestamp is in ms format, see model/timestamp/timestamp.go for
// conversion from time.Time to Prometheus timestamp.
int64 timestamp = 11;
}
// Sparse buckets.
message Buckets {
// A Span is a given number of consecutive buckets at a given
// offset. Logically, it would be more straightforward to include
// the bucket counts in the Span. However, the protobuf
// representation is more compact in the way the data is structured
// here (with all the buckets in a single array separate from the
// Spans).
message Span {
sint32 offset = 1; // Gap to previous span, or starting point for 1st span (which can be negative).
uint32 length = 2; // Length of consecutive buckets.
}
repeated Span span = 1;
// Only one of "delta" or "count" may be used, the former for regular
// histograms with integer counts, the latter for float histograms.
repeated sint64 delta = 2; // Count delta of each bucket compared to previous one (or to zero for 1st bucket).
repeated double count = 3; // Absolute count of each bucket.
}
// TimeSeries represents samples and labels for a single time series.
message TimeSeries {
// For a timeseries to be valid, and for the samples and exemplars
@ -61,6 +120,7 @@ message TimeSeries {
repeated Label labels = 1 [(gogoproto.nullable) = false];
repeated Sample samples = 2 [(gogoproto.nullable) = false];
repeated Exemplar exemplars = 3 [(gogoproto.nullable) = false];
repeated Histogram histograms = 4 [(gogoproto.nullable) = false];
}
message Label {
@ -103,8 +163,9 @@ message Chunk {
// We require this to match chunkenc.Encoding.
enum Encoding {
UNKNOWN = 0;
XOR = 1;
UNKNOWN = 0;
XOR = 1;
HISTOGRAM = 2;
}
Encoding type = 3;
bytes data = 4;