forked from influxdata/influxdb
/
tsi1.go
819 lines (702 loc) · 19.9 KB
/
tsi1.go
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package tsi1
import (
"bytes"
"encoding/binary"
"encoding/hex"
"fmt"
"io"
"os"
"github.com/influxdata/influxdb/influxql"
"github.com/influxdata/influxdb/models"
"github.com/influxdata/influxdb/query"
)
// LoadFactor is the fill percent for RHH indexes.
const LoadFactor = 80
// MeasurementElem represents a generic measurement element.
type MeasurementElem interface {
Name() []byte
Deleted() bool
}
// MeasurementElems represents a list of MeasurementElem.
type MeasurementElems []MeasurementElem
func (a MeasurementElems) Len() int { return len(a) }
func (a MeasurementElems) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
func (a MeasurementElems) Less(i, j int) bool { return bytes.Compare(a[i].Name(), a[j].Name()) == -1 }
// MeasurementIterator represents a iterator over a list of measurements.
type MeasurementIterator interface {
Next() MeasurementElem
}
// MergeMeasurementIterators returns an iterator that merges a set of iterators.
// Iterators that are first in the list take precendence and a deletion by those
// early iterators will invalidate elements by later iterators.
func MergeMeasurementIterators(itrs ...MeasurementIterator) MeasurementIterator {
if len(itrs) == 0 {
return nil
}
return &measurementMergeIterator{
e: make(measurementMergeElem, 0, len(itrs)),
buf: make([]MeasurementElem, len(itrs)),
itrs: itrs,
}
}
type measurementMergeIterator struct {
e measurementMergeElem
buf []MeasurementElem
itrs []MeasurementIterator
}
// Next returns the element with the next lowest name across the iterators.
//
// If multiple iterators contain the same name then the first is returned
// and the remaining ones are skipped.
func (itr *measurementMergeIterator) Next() MeasurementElem {
// Find next lowest name amongst the buffers.
var name []byte
for i, buf := range itr.buf {
// Fill buffer if empty.
if buf == nil {
if buf = itr.itrs[i].Next(); buf != nil {
itr.buf[i] = buf
} else {
continue
}
}
// Find next lowest name.
if name == nil || bytes.Compare(itr.buf[i].Name(), name) == -1 {
name = itr.buf[i].Name()
}
}
// Return nil if no elements remaining.
if name == nil {
return nil
}
// Merge all elements together and clear buffers.
itr.e = itr.e[:0]
for i, buf := range itr.buf {
if buf == nil || !bytes.Equal(buf.Name(), name) {
continue
}
itr.e = append(itr.e, buf)
itr.buf[i] = nil
}
return itr.e
}
// measurementMergeElem represents a merged measurement element.
type measurementMergeElem []MeasurementElem
// Name returns the name of the first element.
func (p measurementMergeElem) Name() []byte {
if len(p) == 0 {
return nil
}
return p[0].Name()
}
// Deleted returns the deleted flag of the first element.
func (p measurementMergeElem) Deleted() bool {
if len(p) == 0 {
return false
}
return p[0].Deleted()
}
// filterUndeletedMeasurementIterator returns all measurements which are not deleted.
type filterUndeletedMeasurementIterator struct {
itr MeasurementIterator
}
// FilterUndeletedMeasurementIterator returns an iterator which filters all deleted measurement.
func FilterUndeletedMeasurementIterator(itr MeasurementIterator) MeasurementIterator {
if itr == nil {
return nil
}
return &filterUndeletedMeasurementIterator{itr: itr}
}
func (itr *filterUndeletedMeasurementIterator) Next() MeasurementElem {
for {
e := itr.itr.Next()
if e == nil {
return nil
} else if e.Deleted() {
continue
}
return e
}
}
// TagKeyElem represents a generic tag key element.
type TagKeyElem interface {
Key() []byte
Deleted() bool
TagValueIterator() TagValueIterator
}
// TagKeyIterator represents a iterator over a list of tag keys.
type TagKeyIterator interface {
Next() TagKeyElem
}
// MergeTagKeyIterators returns an iterator that merges a set of iterators.
// Iterators that are first in the list take precendence and a deletion by those
// early iterators will invalidate elements by later iterators.
func MergeTagKeyIterators(itrs ...TagKeyIterator) TagKeyIterator {
if len(itrs) == 0 {
return nil
}
return &tagKeyMergeIterator{
e: make(tagKeyMergeElem, 0, len(itrs)),
buf: make([]TagKeyElem, len(itrs)),
itrs: itrs,
}
}
type tagKeyMergeIterator struct {
e tagKeyMergeElem
buf []TagKeyElem
itrs []TagKeyIterator
}
// Next returns the element with the next lowest key across the iterators.
//
// If multiple iterators contain the same key then the first is returned
// and the remaining ones are skipped.
func (itr *tagKeyMergeIterator) Next() TagKeyElem {
// Find next lowest key amongst the buffers.
var key []byte
for i, buf := range itr.buf {
// Fill buffer.
if buf == nil {
if buf = itr.itrs[i].Next(); buf != nil {
itr.buf[i] = buf
} else {
continue
}
}
// Find next lowest key.
if key == nil || bytes.Compare(buf.Key(), key) == -1 {
key = buf.Key()
}
}
// Return nil if no elements remaining.
if key == nil {
return nil
}
// Merge elements together & clear buffer.
itr.e = itr.e[:0]
for i, buf := range itr.buf {
if buf == nil || !bytes.Equal(buf.Key(), key) {
continue
}
itr.e = append(itr.e, buf)
itr.buf[i] = nil
}
return itr.e
}
// tagKeyMergeElem represents a merged tag key element.
type tagKeyMergeElem []TagKeyElem
// Key returns the key of the first element.
func (p tagKeyMergeElem) Key() []byte {
if len(p) == 0 {
return nil
}
return p[0].Key()
}
// Deleted returns the deleted flag of the first element.
func (p tagKeyMergeElem) Deleted() bool {
if len(p) == 0 {
return false
}
return p[0].Deleted()
}
// TagValueIterator returns a merge iterator for all elements until a tombstone occurs.
func (p tagKeyMergeElem) TagValueIterator() TagValueIterator {
if len(p) == 0 {
return nil
}
a := make([]TagValueIterator, 0, len(p))
for _, e := range p {
itr := e.TagValueIterator()
a = append(a, itr)
if e.Deleted() {
break
}
}
return MergeTagValueIterators(a...)
}
// TagValueElem represents a generic tag value element.
type TagValueElem interface {
Value() []byte
Deleted() bool
}
// TagValueIterator represents a iterator over a list of tag values.
type TagValueIterator interface {
Next() TagValueElem
}
// MergeTagValueIterators returns an iterator that merges a set of iterators.
// Iterators that are first in the list take precendence and a deletion by those
// early iterators will invalidate elements by later iterators.
func MergeTagValueIterators(itrs ...TagValueIterator) TagValueIterator {
if len(itrs) == 0 {
return nil
}
return &tagValueMergeIterator{
e: make(tagValueMergeElem, 0, len(itrs)),
buf: make([]TagValueElem, len(itrs)),
itrs: itrs,
}
}
type tagValueMergeIterator struct {
e tagValueMergeElem
buf []TagValueElem
itrs []TagValueIterator
}
// Next returns the element with the next lowest value across the iterators.
//
// If multiple iterators contain the same value then the first is returned
// and the remaining ones are skipped.
func (itr *tagValueMergeIterator) Next() TagValueElem {
// Find next lowest value amongst the buffers.
var value []byte
for i, buf := range itr.buf {
// Fill buffer.
if buf == nil {
if buf = itr.itrs[i].Next(); buf != nil {
itr.buf[i] = buf
} else {
continue
}
}
// Find next lowest value.
if value == nil || bytes.Compare(buf.Value(), value) == -1 {
value = buf.Value()
}
}
// Return nil if no elements remaining.
if value == nil {
return nil
}
// Merge elements and clear buffers.
itr.e = itr.e[:0]
for i, buf := range itr.buf {
if buf == nil || !bytes.Equal(buf.Value(), value) {
continue
}
itr.e = append(itr.e, buf)
itr.buf[i] = nil
}
return itr.e
}
// tagValueMergeElem represents a merged tag value element.
type tagValueMergeElem []TagValueElem
// Name returns the value of the first element.
func (p tagValueMergeElem) Value() []byte {
if len(p) == 0 {
return nil
}
return p[0].Value()
}
// Deleted returns the deleted flag of the first element.
func (p tagValueMergeElem) Deleted() bool {
if len(p) == 0 {
return false
}
return p[0].Deleted()
}
// SeriesElem represents a generic series element.
type SeriesElem interface {
Name() []byte
Tags() models.Tags
Deleted() bool
// InfluxQL expression associated with series during filtering.
Expr() influxql.Expr
}
// SeriesElemKey encodes e as a series key.
func SeriesElemKey(e SeriesElem) []byte {
name, tags := e.Name(), e.Tags()
// TODO: Precompute allocation size.
// FIXME: Handle escaping.
var buf []byte
buf = append(buf, name...)
for _, t := range tags {
buf = append(buf, ',')
buf = append(buf, t.Key...)
buf = append(buf, '=')
buf = append(buf, t.Value...)
}
return buf
}
// CompareSeriesElem returns -1 if a < b, 1 if a > b, and 0 if equal.
func CompareSeriesElem(a, b SeriesElem) int {
if cmp := bytes.Compare(a.Name(), b.Name()); cmp != 0 {
return cmp
}
return models.CompareTags(a.Tags(), b.Tags())
}
// seriesElem represents an in-memory implementation of SeriesElem.
type seriesElem struct {
name []byte
tags models.Tags
deleted bool
}
func (e *seriesElem) Name() []byte { return e.name }
func (e *seriesElem) Tags() models.Tags { return e.tags }
func (e *seriesElem) Deleted() bool { return e.deleted }
func (e *seriesElem) Expr() influxql.Expr { return nil }
// SeriesIterator represents a iterator over a list of series.
type SeriesIterator interface {
Next() SeriesElem
}
// MergeSeriesIterators returns an iterator that merges a set of iterators.
// Iterators that are first in the list take precendence and a deletion by those
// early iterators will invalidate elements by later iterators.
func MergeSeriesIterators(itrs ...SeriesIterator) SeriesIterator {
if n := len(itrs); n == 0 {
return nil
} else if n == 1 {
return itrs[0]
}
return &seriesMergeIterator{
buf: make([]SeriesElem, len(itrs)),
itrs: itrs,
}
}
// seriesMergeIterator is an iterator that merges multiple iterators together.
type seriesMergeIterator struct {
buf []SeriesElem
itrs []SeriesIterator
}
// Next returns the element with the next lowest name/tags across the iterators.
//
// If multiple iterators contain the same name/tags then the first is returned
// and the remaining ones are skipped.
func (itr *seriesMergeIterator) Next() SeriesElem {
// Find next lowest name/tags amongst the buffers.
var name []byte
var tags models.Tags
for i, buf := range itr.buf {
// Fill buffer.
if buf == nil {
if buf = itr.itrs[i].Next(); buf != nil {
itr.buf[i] = buf
} else {
continue
}
}
// If the name is not set the pick the first non-empty name.
if name == nil {
name, tags = buf.Name(), buf.Tags()
continue
}
// Set name/tags if they are lower than what has been seen.
if cmp := bytes.Compare(buf.Name(), name); cmp == -1 || (cmp == 0 && models.CompareTags(buf.Tags(), tags) == -1) {
name, tags = buf.Name(), buf.Tags()
}
}
// Return nil if no elements remaining.
if name == nil {
return nil
}
// Refill buffer.
var e SeriesElem
for i, buf := range itr.buf {
if buf == nil || !bytes.Equal(buf.Name(), name) || models.CompareTags(buf.Tags(), tags) != 0 {
continue
}
// Copy first matching buffer to the return buffer.
if e == nil {
e = buf
}
// Clear buffer.
itr.buf[i] = nil
}
return e
}
// IntersectSeriesIterators returns an iterator that only returns series which
// occur in both iterators. If both series have associated expressions then
// they are combined together.
func IntersectSeriesIterators(itr0, itr1 SeriesIterator) SeriesIterator {
if itr0 == nil || itr1 == nil {
return nil
}
return &seriesIntersectIterator{itrs: [2]SeriesIterator{itr0, itr1}}
}
// seriesIntersectIterator is an iterator that merges two iterators together.
type seriesIntersectIterator struct {
e seriesExprElem
buf [2]SeriesElem
itrs [2]SeriesIterator
}
// Next returns the next element which occurs in both iterators.
func (itr *seriesIntersectIterator) Next() (e SeriesElem) {
for {
// Fill buffers.
if itr.buf[0] == nil {
itr.buf[0] = itr.itrs[0].Next()
}
if itr.buf[1] == nil {
itr.buf[1] = itr.itrs[1].Next()
}
// Exit if either buffer is still empty.
if itr.buf[0] == nil || itr.buf[1] == nil {
return nil
}
// Skip if both series are not equal.
if cmp := CompareSeriesElem(itr.buf[0], itr.buf[1]); cmp == -1 {
itr.buf[0] = nil
continue
} else if cmp == 1 {
itr.buf[1] = nil
continue
}
// Merge series together if equal.
itr.e.SeriesElem = itr.buf[0]
// Attach expression.
expr0 := itr.buf[0].Expr()
expr1 := itr.buf[1].Expr()
if expr0 == nil {
itr.e.expr = expr1
} else if expr1 == nil {
itr.e.expr = expr0
} else {
itr.e.expr = influxql.Reduce(&influxql.BinaryExpr{
Op: influxql.AND,
LHS: expr0,
RHS: expr1,
}, nil)
}
itr.buf[0], itr.buf[1] = nil, nil
return &itr.e
}
}
// UnionSeriesIterators returns an iterator that returns series from both
// both iterators. If both series have associated expressions then they are
// combined together.
func UnionSeriesIterators(itr0, itr1 SeriesIterator) SeriesIterator {
// Return other iterator if either one is nil.
if itr0 == nil {
return itr1
} else if itr1 == nil {
return itr0
}
return &seriesUnionIterator{itrs: [2]SeriesIterator{itr0, itr1}}
}
// seriesUnionIterator is an iterator that unions two iterators together.
type seriesUnionIterator struct {
e seriesExprElem
buf [2]SeriesElem
itrs [2]SeriesIterator
}
// Next returns the next element which occurs in both iterators.
func (itr *seriesUnionIterator) Next() (e SeriesElem) {
// Fill buffers.
if itr.buf[0] == nil {
itr.buf[0] = itr.itrs[0].Next()
}
if itr.buf[1] == nil {
itr.buf[1] = itr.itrs[1].Next()
}
// Return the other iterator if either one is empty.
if itr.buf[0] == nil {
e, itr.buf[1] = itr.buf[1], nil
return e
} else if itr.buf[1] == nil {
e, itr.buf[0] = itr.buf[0], nil
return e
}
// Return lesser series.
if cmp := CompareSeriesElem(itr.buf[0], itr.buf[1]); cmp == -1 {
e, itr.buf[0] = itr.buf[0], nil
return e
} else if cmp == 1 {
e, itr.buf[1] = itr.buf[1], nil
return e
}
// Attach element.
itr.e.SeriesElem = itr.buf[0]
// Attach expression.
expr0 := itr.buf[0].Expr()
expr1 := itr.buf[1].Expr()
if expr0 != nil && expr1 != nil {
itr.e.expr = influxql.Reduce(&influxql.BinaryExpr{
Op: influxql.OR,
LHS: expr0,
RHS: expr1,
}, nil)
} else {
itr.e.expr = nil
}
itr.buf[0], itr.buf[1] = nil, nil
return &itr.e
}
// DifferenceSeriesIterators returns an iterator that only returns series which
// occur the first iterator but not the second iterator.
func DifferenceSeriesIterators(itr0, itr1 SeriesIterator) SeriesIterator {
if itr0 != nil && itr1 == nil {
return itr0
} else if itr0 == nil {
return nil
}
return &seriesDifferenceIterator{itrs: [2]SeriesIterator{itr0, itr1}}
}
// seriesDifferenceIterator is an iterator that merges two iterators together.
type seriesDifferenceIterator struct {
buf [2]SeriesElem
itrs [2]SeriesIterator
}
// Next returns the next element which occurs only in the first iterator.
func (itr *seriesDifferenceIterator) Next() (e SeriesElem) {
for {
// Fill buffers.
if itr.buf[0] == nil {
itr.buf[0] = itr.itrs[0].Next()
}
if itr.buf[1] == nil {
itr.buf[1] = itr.itrs[1].Next()
}
// Exit if first buffer is still empty.
if itr.buf[0] == nil {
return nil
} else if itr.buf[1] == nil {
e, itr.buf[0] = itr.buf[0], nil
return e
}
// Return first series if it's less.
// If second series is less then skip it.
// If both series are equal then skip both.
if cmp := CompareSeriesElem(itr.buf[0], itr.buf[1]); cmp == -1 {
e, itr.buf[0] = itr.buf[0], nil
return e
} else if cmp == 1 {
itr.buf[1] = nil
continue
} else {
itr.buf[0], itr.buf[1] = nil, nil
continue
}
}
}
// filterUndeletedSeriesIterator returns all series which are not deleted.
type filterUndeletedSeriesIterator struct {
itr SeriesIterator
}
// FilterUndeletedSeriesIterator returns an iterator which filters all deleted series.
func FilterUndeletedSeriesIterator(itr SeriesIterator) SeriesIterator {
if itr == nil {
return nil
}
return &filterUndeletedSeriesIterator{itr: itr}
}
func (itr *filterUndeletedSeriesIterator) Next() SeriesElem {
for {
e := itr.itr.Next()
if e == nil {
return nil
} else if e.Deleted() {
continue
}
return e
}
}
// seriesExprElem holds a series and its associated filter expression.
type seriesExprElem struct {
SeriesElem
expr influxql.Expr
}
// Expr returns the associated expression.
func (e *seriesExprElem) Expr() influxql.Expr { return e.expr }
// seriesExprIterator is an iterator that attaches an associated expression.
type seriesExprIterator struct {
itr SeriesIterator
e seriesExprElem
}
// newSeriesExprIterator returns a new instance of seriesExprIterator.
func newSeriesExprIterator(itr SeriesIterator, expr influxql.Expr) SeriesIterator {
if itr == nil {
return nil
}
return &seriesExprIterator{
itr: itr,
e: seriesExprElem{
expr: expr,
},
}
}
// Next returns the next element in the iterator.
func (itr *seriesExprIterator) Next() SeriesElem {
itr.e.SeriesElem = itr.itr.Next()
if itr.e.SeriesElem == nil {
return nil
}
return &itr.e
}
// seriesIDIterator represents a iterator over a list of series ids.
type seriesIDIterator interface {
next() uint32
}
// writeTo writes write v into w. Updates n.
func writeTo(w io.Writer, v []byte, n *int64) error {
nn, err := w.Write(v)
*n += int64(nn)
return err
}
// writeUint8To writes write v into w. Updates n.
func writeUint8To(w io.Writer, v uint8, n *int64) error {
nn, err := w.Write([]byte{v})
*n += int64(nn)
return err
}
// writeUint16To writes write v into w using big endian encoding. Updates n.
func writeUint16To(w io.Writer, v uint16, n *int64) error {
var buf [2]byte
binary.BigEndian.PutUint16(buf[:], v)
nn, err := w.Write(buf[:])
*n += int64(nn)
return err
}
// writeUint32To writes write v into w using big endian encoding. Updates n.
func writeUint32To(w io.Writer, v uint32, n *int64) error {
var buf [4]byte
binary.BigEndian.PutUint32(buf[:], v)
nn, err := w.Write(buf[:])
*n += int64(nn)
return err
}
// writeUint64To writes write v into w using big endian encoding. Updates n.
func writeUint64To(w io.Writer, v uint64, n *int64) error {
var buf [8]byte
binary.BigEndian.PutUint64(buf[:], v)
nn, err := w.Write(buf[:])
*n += int64(nn)
return err
}
// writeUvarintTo writes write v into w using variable length encoding. Updates n.
func writeUvarintTo(w io.Writer, v uint64, n *int64) error {
var buf [binary.MaxVarintLen64]byte
i := binary.PutUvarint(buf[:], v)
nn, err := w.Write(buf[:i])
*n += int64(nn)
return err
}
type uint32Slice []uint32
func (a uint32Slice) Len() int { return len(a) }
func (a uint32Slice) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
func (a uint32Slice) Less(i, j int) bool { return a[i] < a[j] }
type uint64Slice []uint64
func (a uint64Slice) Len() int { return len(a) }
func (a uint64Slice) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
func (a uint64Slice) Less(i, j int) bool { return a[i] < a[j] }
type byteSlices [][]byte
func (a byteSlices) Len() int { return len(a) }
func (a byteSlices) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
func (a byteSlices) Less(i, j int) bool { return bytes.Compare(a[i], a[j]) == -1 }
// copyBytes returns a copy of b.
func copyBytes(b []byte) []byte {
if b == nil {
return nil
}
buf := make([]byte, len(b))
copy(buf, b)
return buf
}
// assert will panic with a given formatted message if the given condition is false.
func assert(condition bool, msg string, v ...interface{}) {
if !condition {
panic(fmt.Sprintf("assert failed: "+msg, v...))
}
}
type byTagKey []*query.TagSet
func (t byTagKey) Len() int { return len(t) }
func (t byTagKey) Less(i, j int) bool { return bytes.Compare(t[i].Key, t[j].Key) < 0 }
func (t byTagKey) Swap(i, j int) { t[i], t[j] = t[j], t[i] }
// hexdump is a helper for dumping binary data to stderr.
func hexdump(data []byte) { os.Stderr.Write([]byte(hex.Dump(data))) }