VictoriaMetrics/app/vmselect/promql/timeseries.go
Aliaksandr Valialkin c5f894b361 Makefile: add build and test rules with enabled race detector. These rules have -race suffix
Fix also `unsafe pointer conversion` errors detected by Go1.14. See https://golang.org/doc/go1.14#compiler .
2020-03-05 12:03:38 +02:00

431 lines
12 KiB
Go

package promql
import (
"fmt"
"reflect"
"sort"
"strconv"
"sync"
"unsafe"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
)
type timeseries struct {
MetricName storage.MetricName
Values []float64
Timestamps []int64
// Whether the timeseries may be re-used.
// Timeseries may be re-used only if their members own values
// they refer to.
denyReuse bool
}
func (ts *timeseries) Reset() {
if ts.denyReuse {
*ts = timeseries{}
return
}
ts.MetricName.Reset()
ts.Values = ts.Values[:0]
ts.Timestamps = ts.Timestamps[:0]
}
func (ts *timeseries) String() string {
return fmt.Sprintf("MetricName=%s, Values=%g, Timestamps=%d", &ts.MetricName, ts.Values, ts.Timestamps)
}
func (ts *timeseries) CopyFromShallowTimestamps(src *timeseries) {
ts.Reset()
ts.MetricName.CopyFrom(&src.MetricName)
ts.Values = append(ts.Values[:0], src.Values...)
ts.Timestamps = src.Timestamps
ts.denyReuse = true
}
func (ts *timeseries) CopyFromMetricNames(src *timeseries) {
ts.Reset()
ts.MetricName.CopyFrom(&src.MetricName)
ts.Values = src.Values
ts.Timestamps = src.Timestamps
ts.denyReuse = true
}
func (ts *timeseries) CopyShallow(src *timeseries) {
*ts = *src
ts.denyReuse = true
}
func getTimeseries() *timeseries {
if v := timeseriesPool.Get(); v != nil {
return v.(*timeseries)
}
return &timeseries{}
}
func putTimeseries(ts *timeseries) {
ts.Reset()
timeseriesPool.Put(ts)
}
var timeseriesPool sync.Pool
func marshalTimeseriesFast(dst []byte, tss []*timeseries, maxSize int, step int64) []byte {
if len(tss) == 0 {
logger.Panicf("BUG: tss cannot be empty")
}
// Calculate the required size for marshaled tss.
size := 0
for _, ts := range tss {
size += ts.marshaledFastSizeNoTimestamps()
}
// timestamps are stored only once for all the tss, since they are identical.
assertIdenticalTimestamps(tss, step)
size += 8 * len(tss[0].Timestamps)
if size > maxSize {
// Do not marshal tss, since it would occupy too much space
return dst
}
// Allocate the buffer for the marshaled tss before its' marshaling.
// This should reduce memory fragmentation and memory usage.
dst = bytesutil.Resize(dst, size)
dst = marshalFastTimestamps(dst[:0], tss[0].Timestamps)
for _, ts := range tss {
dst = ts.marshalFastNoTimestamps(dst)
}
return dst
}
// unmarshalTimeseriesFast unmarshals timeseries from src.
//
// The returned timeseries refer to src, so it is unsafe to modify it
// until timeseries are in use.
func unmarshalTimeseriesFast(src []byte) ([]*timeseries, error) {
tail, timestamps, err := unmarshalFastTimestamps(src)
if err != nil {
return nil, err
}
src = tail
var tss []*timeseries
for len(src) > 0 {
var ts timeseries
ts.denyReuse = false
ts.Timestamps = timestamps
tail, err := ts.unmarshalFastNoTimestamps(src)
if err != nil {
return nil, err
}
src = tail
tss = append(tss, &ts)
}
return tss, nil
}
// marshaledFastSizeNoTimestamps returns the size of marshaled ts
// returned from marshalFastNoTimestamps.
func (ts *timeseries) marshaledFastSizeNoTimestamps() int {
mn := &ts.MetricName
n := 2 + len(mn.MetricGroup)
n += 2 // Length of tags.
for i := range mn.Tags {
tag := &mn.Tags[i]
n += 2 + len(tag.Key)
n += 2 + len(tag.Value)
}
n += 8 * len(ts.Values)
return n
}
// marshalFastNoTimestamps appends marshaled ts to dst and returns the result.
//
// It doesn't marshal timestamps.
//
// The result must be unmarshaled with unmarshalFastNoTimestamps.
func (ts *timeseries) marshalFastNoTimestamps(dst []byte) []byte {
mn := &ts.MetricName
dst = marshalBytesFast(dst, mn.MetricGroup)
dst = encoding.MarshalUint16(dst, uint16(len(mn.Tags)))
// There is no need in tags' sorting - they must be sorted after unmarshaling.
for i := range mn.Tags {
tag := &mn.Tags[i]
dst = marshalBytesFast(dst, tag.Key)
dst = marshalBytesFast(dst, tag.Value)
}
// Do not marshal len(ts.Values), since it is already encoded as len(ts.Timestamps)
// during marshalFastTimestamps.
var valuesBuf []byte
if len(ts.Values) > 0 {
valuesBuf = float64ToByteSlice(ts.Values)
}
dst = append(dst, valuesBuf...)
return dst
}
func marshalFastTimestamps(dst []byte, timestamps []int64) []byte {
dst = encoding.MarshalUint32(dst, uint32(len(timestamps)))
var timestampsBuf []byte
if len(timestamps) > 0 {
timestampsBuf = int64ToByteSlice(timestamps)
}
dst = append(dst, timestampsBuf...)
return dst
}
// it is unsafe modifying src while the returned timestamps is in use.
func unmarshalFastTimestamps(src []byte) ([]byte, []int64, error) {
if len(src) < 4 {
return src, nil, fmt.Errorf("cannot decode len(timestamps); got %d bytes; want at least %d bytes", len(src), 4)
}
timestampsCount := int(encoding.UnmarshalUint32(src))
src = src[4:]
if timestampsCount == 0 {
return src, nil, nil
}
bufSize := timestampsCount * 8
if len(src) < bufSize {
return src, nil, fmt.Errorf("cannot unmarshal timestamps; got %d bytes; want at least %d bytes", len(src), bufSize)
}
timestamps := byteSliceToInt64(src[:bufSize])
src = src[bufSize:]
return src, timestamps, nil
}
// unmarshalFastNoTimestamps unmarshals ts from src, so ts members reference src.
//
// It is expected that ts.Timestamps is already unmarshaled.
//
// It is unsafe to modify src while ts is in use.
func (ts *timeseries) unmarshalFastNoTimestamps(src []byte) ([]byte, error) {
// ts members point to src, so they cannot be re-used.
ts.denyReuse = true
tail, err := unmarshalMetricNameFast(&ts.MetricName, src)
if err != nil {
return tail, fmt.Errorf("cannot unmarshal MetricName: %s", err)
}
src = tail
valuesCount := len(ts.Timestamps)
if valuesCount == 0 {
return src, nil
}
bufSize := valuesCount * 8
if len(src) < bufSize {
return src, fmt.Errorf("cannot unmarshal values; got %d bytes; want at least %d bytes", len(src), bufSize)
}
ts.Values = byteSliceToFloat64(src[:bufSize])
return src[bufSize:], nil
}
func float64ToByteSlice(a []float64) (b []byte) {
sh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
sh.Data = uintptr(unsafe.Pointer(&a[0]))
sh.Len = len(a) * int(unsafe.Sizeof(a[0]))
sh.Cap = sh.Len
return
}
func int64ToByteSlice(a []int64) (b []byte) {
sh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
sh.Data = uintptr(unsafe.Pointer(&a[0]))
sh.Len = len(a) * int(unsafe.Sizeof(a[0]))
sh.Cap = sh.Len
return
}
func byteSliceToInt64(b []byte) (a []int64) {
sh := (*reflect.SliceHeader)(unsafe.Pointer(&a))
sh.Data = uintptr(unsafe.Pointer(&b[0]))
sh.Len = len(b) / int(unsafe.Sizeof(a[0]))
sh.Cap = sh.Len
return
}
func byteSliceToFloat64(b []byte) (a []float64) {
sh := (*reflect.SliceHeader)(unsafe.Pointer(&a))
sh.Data = uintptr(unsafe.Pointer(&b[0]))
sh.Len = len(b) / int(unsafe.Sizeof(a[0]))
sh.Cap = sh.Len
return
}
// unmarshalMetricNameFast unmarshals mn from src, so mn members
// hold references to src.
//
// It is unsafe modifying src while mn is in use.
func unmarshalMetricNameFast(mn *storage.MetricName, src []byte) ([]byte, error) {
mn.Reset()
tail, metricGroup, err := unmarshalBytesFast(src)
if err != nil {
return tail, fmt.Errorf("cannot unmarshal MetricGroup: %s", err)
}
src = tail
mn.MetricGroup = metricGroup[:len(metricGroup):len(metricGroup)]
if len(src) < 2 {
return src, fmt.Errorf("not enough bytes for unmarshaling len(tags); need at least 2 bytes; got %d bytes", len(src))
}
tagsLen := encoding.UnmarshalUint16(src)
src = src[2:]
if n := int(tagsLen) - cap(mn.Tags); n > 0 {
mn.Tags = append(mn.Tags[:cap(mn.Tags)], make([]storage.Tag, n)...)
}
mn.Tags = mn.Tags[:tagsLen]
for i := range mn.Tags {
tail, key, err := unmarshalBytesFast(src)
if err != nil {
return tail, fmt.Errorf("cannot unmarshal key for tag[%d]: %s", i, err)
}
src = tail
tail, value, err := unmarshalBytesFast(src)
if err != nil {
return tail, fmt.Errorf("cannot unmarshal value for tag[%d]: %s", i, err)
}
src = tail
tag := &mn.Tags[i]
tag.Key = key[:len(key):len(key)]
tag.Value = value[:len(value):len(value)]
}
return src, nil
}
func marshalMetricTagsFast(dst []byte, tags []storage.Tag) []byte {
for i := range tags {
tag := &tags[i]
dst = marshalBytesFast(dst, tag.Key)
dst = marshalBytesFast(dst, tag.Value)
}
return dst
}
func marshalMetricNameSorted(dst []byte, mn *storage.MetricName) []byte {
dst = marshalBytesFast(dst, mn.MetricGroup)
sortMetricTags(mn.Tags)
dst = marshalMetricTagsFast(dst, mn.Tags)
return dst
}
func marshalMetricTagsSorted(dst []byte, mn *storage.MetricName) []byte {
sortMetricTags(mn.Tags)
return marshalMetricTagsFast(dst, mn.Tags)
}
func sortMetricTags(tags []storage.Tag) {
less := func(i, j int) bool {
return string(tags[i].Key) < string(tags[j].Key)
}
if sort.SliceIsSorted(tags, less) {
return
}
sort.Slice(tags, less)
}
func marshalBytesFast(dst []byte, s []byte) []byte {
dst = encoding.MarshalUint16(dst, uint16(len(s)))
dst = append(dst, s...)
return dst
}
func unmarshalBytesFast(src []byte) ([]byte, []byte, error) {
if len(src) < 2 {
return src, nil, fmt.Errorf("cannot decode size form src=%X; it must be at least 2 bytes", src)
}
n := encoding.UnmarshalUint16(src)
src = src[2:]
if len(src) < int(n) {
return src, nil, fmt.Errorf("too short src=%X; it must be at least %d bytes", src, n)
}
return src[n:], src[:n], nil
}
func stringMetricName(mn *storage.MetricName) string {
var dst []byte
dst = append(dst, mn.MetricGroup...)
sortMetricTags(mn.Tags)
dst = appendStringMetricTags(dst, mn.Tags)
return string(dst)
}
func stringMetricTags(mn *storage.MetricName) string {
var dst []byte
sortMetricTags(mn.Tags)
dst = appendStringMetricTags(dst, mn.Tags)
return string(dst)
}
func appendStringMetricTags(dst []byte, tags []storage.Tag) []byte {
dst = append(dst, '{')
for i := range tags {
tag := &tags[i]
dst = append(dst, tag.Key...)
dst = append(dst, '=')
value := bytesutil.ToUnsafeString(tag.Value)
dst = strconv.AppendQuote(dst, value)
if i+1 < len(tags) {
dst = append(dst, ", "...)
}
}
dst = append(dst, '}')
return dst
}
func assertIdenticalTimestamps(tss []*timeseries, step int64) {
if len(tss) == 0 {
return
}
tsGolden := tss[0]
if len(tsGolden.Values) != len(tsGolden.Timestamps) {
logger.Panicf("BUG: len(tsGolden.Values) must match len(tsGolden.Timestamps); got %d vs %d", len(tsGolden.Values), len(tsGolden.Timestamps))
}
if len(tsGolden.Timestamps) > 0 {
prevTimestamp := tsGolden.Timestamps[0]
for _, timestamp := range tsGolden.Timestamps[1:] {
if timestamp-prevTimestamp != step {
logger.Panicf("BUG: invalid step between timestamps; got %d; want %d; tsGolden.Timestamps=%d", timestamp-prevTimestamp, step, tsGolden.Timestamps)
}
prevTimestamp = timestamp
}
}
for _, ts := range tss {
if len(ts.Values) != len(tsGolden.Values) {
logger.Panicf("BUG: unexpected len(ts.Values); got %d; want %d; ts.Values=%g", len(ts.Values), len(tsGolden.Values), ts.Values)
}
if len(ts.Timestamps) != len(tsGolden.Timestamps) {
logger.Panicf("BUG: unexpected len(ts.Timestamps); got %d; want %d; ts.Timestamps=%d", len(ts.Timestamps), len(tsGolden.Timestamps), ts.Timestamps)
}
if len(ts.Timestamps) == 0 {
continue
}
if &ts.Timestamps[0] == &tsGolden.Timestamps[0] {
// Fast path - shared timestamps.
continue
}
for i := range ts.Timestamps {
if ts.Timestamps[i] != tsGolden.Timestamps[i] {
logger.Panicf("BUG: timestamps mismatch at position %d; got %d; want %d; ts.Timestamps=%d, tsGolden.Timestamps=%d",
i, ts.Timestamps[i], tsGolden.Timestamps[i], ts.Timestamps, tsGolden.Timestamps)
}
}
}
}