store: Optimized labels conversion on store.Series; Added unsafe labe…

…ls conversion.

## Changes

* method TranslateLables CPU Optimized (streamed sorting).
* All store GW label conversation to []storepb.Label are now alloc-less.

```
go test -bench=BenchmarkUnsafeVSSafeLabelsConversion -run=^$ -benchmem -timeout 2h -benchtime 10s ./pkg/store/storepb/...
 goos: linux
 goarch: amd64
 pkg: github.com/thanos-io/thanos/pkg/store/storepb
 BenchmarkUnsafeVSSafeLabelsConversion/safe-12         	   34822	    339076 ns/op	  655368 B/op	       2 allocs/op
 BenchmarkUnsafeVSSafeLabelsConversion/unsafe-12       	1000000000	         2.32 ns/op	       0 B/op	       0 allocs/op
PASS
```

TODO: Do the same on Querier.

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

go.mod

@@ -51,7 +51,7 @@ require (
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
 	golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e
 	golang.org/x/text v0.3.2
-	golang.org/x/tools v0.0.0-20200221224223-e1da425f72fd // indirect
+	golang.org/x/tools v0.0.0-20200306191617-51e69f71924f // indirect
 	google.golang.org/api v0.14.0
 	google.golang.org/genproto v0.0.0-20191115194625-c23dd37a84c9
 	google.golang.org/grpc v1.25.1

go.sum

@@ -771,8 +771,8 @@ golang.org/x/mobile v0.0.0-20190312151609-d3739f865fa6/go.mod h1:z+o9i4GpDbdi3rU
 golang.org/x/mobile v0.0.0-20190719004257-d2bd2a29d028/go.mod h1:E/iHnbuqvinMTCcRqshq8CkpyQDoeVncDDYHnLhea+o=
 golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=
 golang.org/x/mod v0.1.0/go.mod h1:0QHyrYULN0/3qlju5TqG8bIK38QM8yzMo5ekMj3DlcY=
-golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee h1:WG0RUwxtNT4qqaXX3DPA8zHFNm/D9xaBpxzHt1WcA/E=
-golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
+golang.org/x/mod v0.2.0 h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=
+golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -803,6 +803,8 @@ golang.org/x/net v0.0.0-20191002035440-2ec189313ef0/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20191004110552-13f9640d40b9/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20191112182307-2180aed22343 h1:00ohfJ4K98s3m6BGUoBd8nyfp4Yl0GoIKvw5abItTjI=
 golang.org/x/net v0.0.0-20191112182307-2180aed22343/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200226121028-0de0cce0169b h1:0mm1VjtFUOIlE1SbDlwjYaDxZVDP2S5ou6y0gSgXHu8=
+golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20181106182150-f42d05182288/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -897,8 +899,9 @@ golang.org/x/tools v0.0.0-20191111182352-50fa39b762bc/go.mod h1:b+2E5dAYhXwXZwtn
 golang.org/x/tools v0.0.0-20191113191852-77e3bb0ad9e7/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191115202509-3a792d9c32b2 h1:EtTFh6h4SAKemS+CURDMTDIANuduG5zKEXShyy18bGA=
 golang.org/x/tools v0.0.0-20191115202509-3a792d9c32b2/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.0.0-20200221224223-e1da425f72fd h1:hHkvGJK23seRCflePJnVa9IMv8fsuavSCWKd11kDQFs=
-golang.org/x/tools v0.0.0-20200221224223-e1da425f72fd/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20200306191617-51e69f71924f h1:bFIWQKTZ5vXyr7xMDvzbWUj5Y/WBE4a4sf35MAyZjx0=
+golang.org/x/tools v0.0.0-20200306191617-51e69f71924f/go.mod h1:o4KQGtdN14AW+yjsvvwRTJJuXz8XRtIHtEnmAXLyFUw=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=

pkg/receive/handler.go

@@ -23,9 +23,9 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/route"
-	"github.com/prometheus/prometheus/prompb"
 	"github.com/prometheus/prometheus/storage"
 	terrors "github.com/prometheus/prometheus/tsdb/errors"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"

pkg/receive/handler_test.go

@@ -19,12 +19,11 @@ import (
 	"github.com/golang/snappy"
 	"github.com/pkg/errors"
 	"github.com/prometheus/prometheus/pkg/labels"
-	"github.com/prometheus/prometheus/prompb"
 	"github.com/prometheus/prometheus/storage"
 	terrors "github.com/prometheus/prometheus/tsdb/errors"
-	"google.golang.org/grpc"
-
 	"github.com/thanos-io/thanos/pkg/store/storepb"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
+	"google.golang.org/grpc"
 )
 
 func TestCountCause(t *testing.T) {

pkg/receive/hashring.go

@@ -11,7 +11,7 @@ import (
 
 	"github.com/cespare/xxhash"
 	"github.com/pkg/errors"
-	"github.com/prometheus/prometheus/prompb"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 )
 
 const sep = '\xff'

pkg/receive/hashring_test.go

@@ -6,7 +6,7 @@ package receive
 import (
 	"testing"
 
-	"github.com/prometheus/prometheus/prompb"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 )
 
 func TestHash(t *testing.T) {

pkg/receive/writer.go

@@ -9,11 +9,10 @@ import (
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/log/level"
 	"github.com/pkg/errors"
-	"github.com/prometheus/prometheus/prompb"
-
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/prometheus/prometheus/storage"
 	terrors "github.com/prometheus/prometheus/tsdb/errors"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 )
 
 // Appendable returns an Appender.

pkg/store/prometheus.go

@@ -29,13 +29,13 @@ import (
 	"github.com/prometheus/common/version"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/prometheus/prometheus/pkg/timestamp"
-	"github.com/prometheus/prometheus/prompb"
 	"github.com/prometheus/prometheus/storage/remote"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
 	"github.com/thanos-io/thanos/pkg/component"
 	"github.com/thanos-io/thanos/pkg/exthttp"
 	"github.com/thanos-io/thanos/pkg/runutil"
 	"github.com/thanos-io/thanos/pkg/store/storepb"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 	"github.com/thanos-io/thanos/pkg/tracing"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
@@ -178,12 +178,7 @@ func (p *PrometheusStore) Series(r *storepb.SeriesRequest, s storepb.Store_Serie
 			for k, v := range lbm {
 				lset = append(lset, storepb.Label{Name: k, Value: v})
 			}
-			for _, l := range externalLabels {
-				lset = append(lset, storepb.Label{
-					Name:  l.Name,
-					Value: l.Value,
-				})
-			}
+			lset = append(lset, storepb.PromLabelsToLabelsUnsafe(externalLabels)...)
 			sort.Slice(lset, func(i, j int) bool {
 				return lset[i].Name < lset[j].Name
 			})
@@ -518,32 +513,34 @@ func (p *PrometheusStore) encodeChunk(ss []prompb.Sample) (storepb.Chunk_Encodin
 
 // translateAndExtendLabels transforms a metrics into a protobuf label set. It additionally
 // attaches the given labels to it, overwriting existing ones on collision.
+// Both input labels are expected to be sorted.
+//
+// NOTE(bwplotka): Don't use modify passed slices as we reuse underlying memory.
 func (p *PrometheusStore) translateAndExtendLabels(m []prompb.Label, extend labels.Labels) []storepb.Label {
+	pbLabels := storepb.PrompbLabelsToLabelsUnsafe(m)
+	pbExtend := storepb.PromLabelsToLabelsUnsafe(extend)
+
 	lset := make([]storepb.Label, 0, len(m)+len(extend))
+	ei := 0
 
-	for _, l := range m {
-		if extend.Get(l.Name) != "" {
-			continue
+Outer:
+	for _, l := range pbLabels {
+		for ei < len(pbExtend) {
+			if l.Name < pbExtend[ei].Name {
+				break
+			}
+			lset = append(lset, pbExtend[ei])
+			ei++
+			if l.Name == pbExtend[ei-1].Name {
+				continue Outer
+			}
 		}
-		lset = append(lset, storepb.Label{
-			Name:  l.Name,
-			Value: l.Value,
-		})
+		lset = append(lset, l)
 	}
-
-	return extendLset(lset, extend)
-}
-
-func extendLset(lset []storepb.Label, extend labels.Labels) []storepb.Label {
-	for _, l := range extend {
-		lset = append(lset, storepb.Label{
-			Name:  l.Name,
-			Value: l.Value,
-		})
+	for ei < len(pbExtend) {
+		lset = append(lset, pbExtend[ei])
+		ei++
 	}
-	sort.Slice(lset, func(i, j int) bool {
-		return lset[i].Name < lset[j].Name
-	})
 	return lset
 }
 

pkg/store/prometheus_test.go

@@ -14,13 +14,13 @@ import (
 	"github.com/fortytw2/leaktest"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/prometheus/prometheus/pkg/timestamp"
-	"github.com/prometheus/prometheus/prompb"
 	"github.com/prometheus/prometheus/tsdb"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
 	"github.com/thanos-io/thanos/pkg/testutil/e2eutil"
 
 	"github.com/thanos-io/thanos/pkg/component"
 	"github.com/thanos-io/thanos/pkg/store/storepb"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 	"github.com/thanos-io/thanos/pkg/testutil"
 )
 

pkg/store/storepb/custom.go

@@ -5,8 +5,10 @@ package storepb
 
 import (
 	"strings"
+	"unsafe"
 
 	"github.com/prometheus/prometheus/pkg/labels"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 )
 
 var PartialResponseStrategyValues = func() []string {
@@ -166,15 +168,57 @@ func (s *mergedSeriesSet) Next() bool {
 	return true
 }
 
+// LabelsToPromLabels converts Thanos proto labels to Prometheus labels in type safe manner.
 func LabelsToPromLabels(lset []Label) labels.Labels {
 	ret := make(labels.Labels, len(lset))
 	for i, l := range lset {
 		ret[i] = labels.Label{Name: l.Name, Value: l.Value}
 	}
+	return ret
+}
+
+// LabelsToPromLabelsUnsafe converts Thanos proto labels to Prometheus labels in type unsafe manner.
+// It reuses the same memory. Caller should abort using passed []Labels.
+//
+// NOTE: This depends on order of struct fields etc, so use with extreme care.
+func LabelsToPromLabelsUnsafe(lset []Label) labels.Labels {
+	return *(*[]labels.Label)(unsafe.Pointer(&lset))
+}
 
+// PromLabelsToLabels converts Prometheus labels to Thanos proto labels in type safe manner.
+func PromLabelsToLabels(lset labels.Labels) []Label {
+	ret := make([]Label, len(lset))
+	for i, l := range lset {
+		ret[i] = Label{Name: l.Name, Value: l.Value}
+	}
 	return ret
 }
 
+// PromLabelsToLabelsUnsafe converts Prometheus labels to Thanos proto labels in type unsafe manner.
+// It reuses the same memory. Caller should abort using passed labels.Labels.
+//
+// // NOTE: This depends on order of struct fields etc, so use with extreme care.
+func PromLabelsToLabelsUnsafe(lset labels.Labels) []Label {
+	return *(*[]Label)(unsafe.Pointer(&lset))
+}
+
+// PrompbLabelsToLabels converts Prometheus labels to Thanos proto labels in type safe manner.
+func PrompbLabelsToLabels(lset []prompb.Label) []Label {
+	ret := make([]Label, len(lset))
+	for i, l := range lset {
+		ret[i] = Label{Name: l.Name, Value: l.Value}
+	}
+	return ret
+}
+
+// PrompbLabelsToLabelsUnsafe converts Prometheus proto labels to Thanos proto labels in type unsafe manner.
+// It reuses the same memory. Caller should abort using passed labels.Labels.
+//
+// // NOTE: This depends on order of struct fields etc, so use with extreme care.
+func PrompbLabelsToLabelsUnsafe(lset []prompb.Label) []Label {
+	return *(*[]Label)(unsafe.Pointer(&lset))
+}
+
 func LabelsToString(lset []Label) string {
 	var s []string
 	for _, l := range lset {

pkg/store/storepb/custom_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
+	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
@@ -328,3 +329,58 @@ func BenchmarkMergedSeriesSet(b *testing.B) {
 		}
 	}
 }
+
+var testLsetMap = map[string]string{
+	"a":                           "1",
+	"c":                           "2",
+	"d":                           "dsfsdfsdfsdf123414234",
+	"124134235423534534ffdasdfsf": "1",
+	"":                            "",
+	"b":                           "",
+}
+
+func TestPromLabelsToLabelsUnsafe(t *testing.T) {
+	testutil.Equals(t, PromLabelsToLabels(labels.FromMap(testLsetMap)), PromLabelsToLabelsUnsafe(labels.FromMap(testLsetMap)))
+}
+
+func TestLabelsToPromLabelsUnsafe(t *testing.T) {
+	testutil.Equals(t, labels.FromMap(testLsetMap), LabelsToPromLabels(PromLabelsToLabels(labels.FromMap(testLsetMap))))
+	testutil.Equals(t, labels.FromMap(testLsetMap), LabelsToPromLabelsUnsafe(PromLabelsToLabels(labels.FromMap(testLsetMap))))
+}
+
+func TestPrompbLabelsToLabelsUnsafe(t *testing.T) {
+	var pb []prompb.Label
+	for _, l := range labels.FromMap(testLsetMap) {
+		pb = append(pb, prompb.Label{Name: l.Name, Value: l.Value})
+	}
+	testutil.Equals(t, PromLabelsToLabels(labels.FromMap(testLsetMap)), PrompbLabelsToLabels(pb))
+	testutil.Equals(t, PromLabelsToLabels(labels.FromMap(testLsetMap)), PrompbLabelsToLabelsUnsafe(pb))
+}
+
+func BenchmarkUnsafeVSSafeLabelsConversion(b *testing.B) {
+	const (
+		fmtLbl = "%07daaaaaaaaaabbbbbbbbbbccccccccccdddddddddd"
+		num    = 10000
+	)
+	lbls := make([]labels.Label, 0, num)
+	for i := 0; i < num; i++ {
+		lbls = append(lbls, labels.Label{Name: fmt.Sprintf(fmtLbl, i), Value: fmt.Sprintf(fmtLbl, i)})
+	}
+
+	var converted labels.Labels
+	b.Run("safe", func(b *testing.B) {
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			converted = LabelsToPromLabels(PromLabelsToLabels(lbls))
+		}
+	})
+	testutil.Equals(b, num, len(converted))
+	b.Run("unsafe", func(b *testing.B) {
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			converted = LabelsToPromLabelsUnsafe(PromLabelsToLabelsUnsafe(lbls))
+		}
+	})
+	testutil.Equals(b, num, len(converted))
+
+}

pkg/store/storepb/prompb/README.md

@@ -0,0 +1,11 @@
+NOTE(bwplotka): This excerpt of "github.com/prometheus/prometheus/prompb" reconstructed to avoid XXX fields for unsafe conversion to safe allocs.
+
+The compiled protobufs are version controlled and you won't normally need to
+re-compile them when building Prometheus.
+
+If however you have modified the defs and do need to re-compile, run
+`make proto` from the parent dir.
+
+In order for the script to run, you'll need `protoc` (version 3.5.1) in your
+PATH.
+