7 Commits (f24dc17fcc0c7943b3edeffa36f8dba77fda0db7)

Author	SHA1	Message	Date
Marc Tudurí	9474610baf	Support FloatHistogram in TSDB (#11522) ... Extends Appender.AppendHistogram function to accept the FloatHistogram. TSDB supports appending, querying, WAL replay, for this new type of histogram. Signed-off-by: Marc Tudurí <marctc@protonmail.com> Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com> Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>	3 years ago
Björn Rabenstein	dccfb9db4e	histogram: Remove code replication via generics (#11361) ... * histogram: Simplify iterators We don't really need currLower and currUpper and can calculate it when needed (as already done for the floatBucketIterator). The calculation is cheap, while keeping those extra variables around costs RAM (potentially a lot with many iterators). * histogram: Convert Bucket/FloatBucket to one generic type * histogram: Move some bucket iterator code into generic base iterator * histogram: Remove cumulative iterator for FloatHistogram We added it in the past for completeness (Histogram has one), but it has never been used. Plus, even the cumulative iterator for Histogram is only there for test reasons. We can always add it back, and then maybe even using generics. Signed-off-by: beorn7 <beorn@grafana.com>	4 years ago
beorn7	a7c519930e	histograms: Add Compact method to the normal integer Histogram ... And use the new method to call to compact Histograms during parsing. This happens for both `Histogram` and `FloatHistogram`. In this way, if targets decide to optimize the exposition size by merging spans with empty buckets in between, we still get a normalized results. It will also normalize away any valid but weird representations like empty spans, spans with offset zero, and empty buckets at the start or end of a span. The implementation seemed easy at first as it just turns the `compactBuckets` helper into a generic function (which now got its own file). However, the integer Histograms have delta buckets instead of absolute buckets, which had to be treated specially in the generic `compactBuckets` function. To make sure it works, I have added plenty of explicit tests for `Histogram` in addition to the `FloatHistogram` tests. I have also updated the doc comment for the `Compact` method. Based on the insights now expressed in the doc comment, compacting with a maxEmptyBuckets > 0 is rarely useful. Therefore, this commit also sets the value to 0 in the two cases we were using 3 so far. We might still want to reconsider, so I don't want to remove the maxEmptyBuckets parameter right now. Signed-off-by: beorn7 <beorn@grafana.com>	4 years ago
Ganesh Vernekar	2474c6fb2c	Error on amending histograms on append (#11308) ... * Error on amending histograms on append Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com> * Rename Matches to Equals Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com> Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>	4 years ago
beorn7	6a820a646c	histogram: Add FloatHistogram ... Including a few adjustments for normal Histogram, too, e.g. use pointer receiver to avoid the large copy on method calls. Signed-off-by: beorn7 <beorn@grafana.com>	5 years ago
beorn7	f1065e44a4	model: String method for histogram.Histogram ... This includes a regular bucket iterator and a string method for histogram.Bucket. Signed-off-by: beorn7 <beorn@grafana.com>	5 years ago
beorn7	7a8bb8222c	Style cleanup of all the changes in sparsehistogram so far ... A lot of this code was hacked together, literally during a hackathon. This commit intends not to change the code substantially, but just make the code obey the usual style practices. A (possibly incomplete) list of areas: * Generally address linter warnings. * The `pgk` directory is deprecated as per dev-summit. No new packages should be added to it. I moved the new `pkg/histogram` package to `model` anticipating what's proposed in #9478. * Make the naming of the Sparse Histogram more consistent. Including abbreviations, there were just too many names for it: SparseHistogram, Histogram, Histo, hist, his, shs, h. The idea is to call it "Histogram" in general. Only add "Sparse" if it is needed to avoid confusion with conventional Histograms (which is rare because the TSDB really has no notion of conventional Histograms). Use abbreviations only in local scope, and then really abbreviate (not just removing three out of seven letters like in "Histo"). This is in the spirit of https://github.com/golang/go/wiki/CodeReviewComments#variable-names * Several other minor name changes. * A lot of formatting of doc comments. For one, following https://github.com/golang/go/wiki/CodeReviewComments#comment-sentences , but also layout question, anticipating how things will look like when rendered by `godoc` (even where `godoc` doesn't render them right now because they are for unexported types or not a doc comment at all but just a normal code comment - consistency is queen!). * Re-enabled `TestQueryLog` and `TestEndopints` (they pass now, leaving them disabled was presumably an oversight). * Bucket iterator for histogram.Histogram is now created with a method. * HistogramChunk.iterator now allows iterator recycling. (I think @dieterbe only commented it out because he was confused by the question in the comment.) * HistogramAppender.Append panics now because we decided to treat staleness marker differently. Signed-off-by: beorn7 <beorn@grafana.com>	5 years ago