prometheus/storage/buffer_test.go
Bartlomiej Plotka d5c33877f9
storage: Added Chunks{Queryable/Querier/SeriesSet/Series/Iteratable. Added generic Merge{SeriesSet/Querier} implementation. (#7005)
* storage: Added Chunks{Queryable/Querier/SeriesSet/Series/Iteratable. Added generic Merge{SeriesSet/Querier} implementation.

## Rationales:

In many places (e.g. chunk Remote read, Thanos Receive fetching chunk from TSDB), we operate on encoded chunks not samples.
This means that we unnecessary decode/encode, wasting CPU, time and memory.
This PR adds chunk iterator interfaces and makes the merge code to be reused between both seriesSets

I will make the use of it in following PR inside tsdb itself. For now fanout implements it and mergers.

All merges now also allows passing series mergers. This opens doors for custom deduplications other than TSDB vertical ones (e.g. offline one we have in Thanos).

## Changes

* Added Chunk versions of all iterating methods. It all starts in Querier/ChunkQuerier. The plan is that
Storage will implement both chunked and samples.
* Added Seek to chunks.Iterator interface for iterating over chunks.
* NewMergeChunkQuerier was added; Both this and NewMergeQuerier are now using generigMergeQuerier to share the code. Generic code was added.
* Improved tests.
* Added some TODO for further simplifications in next PRs.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Addressed Brian's comments.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Moved s/Labeled/SeriesLabels as per Krasi suggestion.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Addressed Krasi's comments.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Second iteration of Krasi comments.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Another round of comments.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
2020-03-24 20:15:47 +00:00

215 lines
5 KiB
Go

// Copyright 2017 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package storage
import (
"math/rand"
"testing"
"github.com/prometheus/prometheus/tsdb/tsdbutil"
"github.com/prometheus/prometheus/util/testutil"
)
func TestSampleRing(t *testing.T) {
cases := []struct {
input []int64
delta int64
size int
}{
{
input: []int64{1, 2, 3, 4, 5, 6, 7, 8, 9, 10},
delta: 2,
size: 1,
},
{
input: []int64{1, 2, 3, 4, 5, 6, 7, 8, 9, 10},
delta: 2,
size: 2,
},
{
input: []int64{1, 2, 3, 4, 5, 6, 7, 8, 9, 10},
delta: 7,
size: 3,
},
{
input: []int64{1, 2, 3, 4, 5, 16, 17, 18, 19, 20},
delta: 7,
size: 1,
},
{
input: []int64{1, 2, 3, 4, 6},
delta: 4,
size: 4,
},
}
for _, c := range cases {
r := newSampleRing(c.delta, c.size)
input := []sample{}
for _, t := range c.input {
input = append(input, sample{
t: t,
v: float64(rand.Intn(100)),
})
}
for i, s := range input {
r.add(s.t, s.v)
buffered := r.samples()
for _, sold := range input[:i] {
found := false
for _, bs := range buffered {
if bs.t == sold.t && bs.v == sold.v {
found = true
break
}
}
if found {
testutil.Assert(t, sold.t >= s.t-c.delta, "%d: unexpected sample %d in buffer; buffer %v", i, sold.t, buffered)
} else {
testutil.Assert(t, sold.t < s.t-c.delta, "%d: expected sample %d to be in buffer but was not; buffer %v", i, sold.t, buffered)
}
}
}
}
}
func TestBufferedSeriesIterator(t *testing.T) {
var it *BufferedSeriesIterator
bufferEq := func(exp []sample) {
var b []sample
bit := it.Buffer()
for bit.Next() {
t, v := bit.At()
b = append(b, sample{t: t, v: v})
}
testutil.Equals(t, exp, b, "buffer mismatch")
}
sampleEq := func(ets int64, ev float64) {
ts, v := it.Values()
testutil.Equals(t, ets, ts, "timestamp mismatch")
testutil.Equals(t, ev, v, "value mismatch")
}
it = NewBufferIterator(NewListSeriesIterator([]tsdbutil.Sample{
sample{t: 1, v: 2},
sample{t: 2, v: 3},
sample{t: 3, v: 4},
sample{t: 4, v: 5},
sample{t: 5, v: 6},
sample{t: 99, v: 8},
sample{t: 100, v: 9},
sample{t: 101, v: 10},
}), 2)
testutil.Assert(t, it.Seek(-123), "seek failed")
sampleEq(1, 2)
bufferEq(nil)
testutil.Assert(t, it.Next(), "next failed")
sampleEq(2, 3)
bufferEq([]sample{{t: 1, v: 2}})
testutil.Assert(t, it.Next(), "next failed")
testutil.Assert(t, it.Next(), "next failed")
testutil.Assert(t, it.Next(), "next failed")
sampleEq(5, 6)
bufferEq([]sample{{t: 2, v: 3}, {t: 3, v: 4}, {t: 4, v: 5}})
testutil.Assert(t, it.Seek(5), "seek failed")
sampleEq(5, 6)
bufferEq([]sample{{t: 2, v: 3}, {t: 3, v: 4}, {t: 4, v: 5}})
testutil.Assert(t, it.Seek(101), "seek failed")
sampleEq(101, 10)
bufferEq([]sample{{t: 99, v: 8}, {t: 100, v: 9}})
testutil.Assert(t, !it.Next(), "next succeeded unexpectedly")
}
// At() should not be called once Next() returns false.
func TestBufferedSeriesIteratorNoBadAt(t *testing.T) {
done := false
m := &mockSeriesIterator{
seek: func(int64) bool { return false },
at: func() (int64, float64) {
testutil.Assert(t, !done, "unexpectedly done")
done = true
return 0, 0
},
next: func() bool { return !done },
err: func() error { return nil },
}
it := NewBufferIterator(m, 60)
it.Next()
it.Next()
}
func BenchmarkBufferedSeriesIterator(b *testing.B) {
// Simulate a 5 minute rate.
it := NewBufferIterator(newFakeSeriesIterator(int64(b.N), 30), 5*60)
b.SetBytes(int64(b.N * 16))
b.ReportAllocs()
b.ResetTimer()
for it.Next() {
// scan everything
}
testutil.Ok(b, it.Err())
}
type mockSeriesIterator struct {
seek func(int64) bool
at func() (int64, float64)
next func() bool
err func() error
}
func (m *mockSeriesIterator) Seek(t int64) bool { return m.seek(t) }
func (m *mockSeriesIterator) At() (int64, float64) { return m.at() }
func (m *mockSeriesIterator) Next() bool { return m.next() }
func (m *mockSeriesIterator) Err() error { return m.err() }
type fakeSeriesIterator struct {
nsamples int64
step int64
idx int64
}
func newFakeSeriesIterator(nsamples, step int64) *fakeSeriesIterator {
return &fakeSeriesIterator{nsamples: nsamples, step: step, idx: -1}
}
func (it *fakeSeriesIterator) At() (int64, float64) {
return it.idx * it.step, 123 // value doesn't matter
}
func (it *fakeSeriesIterator) Next() bool {
it.idx++
return it.idx < it.nsamples
}
func (it *fakeSeriesIterator) Seek(t int64) bool {
it.idx = t / it.step
return it.idx < it.nsamples
}
func (it *fakeSeriesIterator) Err() error { return nil }