VictoriaMetrics/lib/logstorage/rows.go
Aliaksandr Valialkin 8dce4eb189
lib/logstorage: follow-up for 94627113db
- Move uniqueFields from rows to blockStreamMerger struct.
  This allows localizing all the references to uniqueFields inside blockStreamMerger.mustWriteBlock(),
  which should improve readability and maintainability of the code.

- Remove logging of the event when blocks cannot be merged because they contain more than maxColumnsPerBlock,
  since the provided logging didn't provide the solution for the issue with too many columns.
  I couldn't figure out the proper solution, which could be helpful for end user,
  so decided to remove the logging until we find the solution.

This commit also contains the following additional changes:

- It truncates field names longer than 128 chars during logs ingestion.
  This should prevent from ingesting bogus field names.
  This also should prevent from too big columnsHeader blocks,
  which could negatively affect search query performance,
  since columnsHeader is read on every scan of the corresponding data block.

- It limits the maximum length of const column value to 256.
  Longer values are stored in an ordinary columns.
  This helps limiting the size of columnsHeader blocks
  and improving search query performance by avoiding
  reading too long const columns on every scan of the corresponding data block.

- It deduplicates columns with identical names during data ingestion
  and background merging. Previously it was possible to pass columns with duplicate names
  to block.mustInitFromRows(), and they were stored as is in the block.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4762
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4969
2023-10-02 19:19:08 +02:00

123 lines
2.8 KiB
Go

package logstorage
import (
"fmt"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
)
// Field is a single field for the log entry.
type Field struct {
// Name is the name of the field
Name string
// Value is the value of the field
Value string
}
// Reset resets f for future re-use.
func (f *Field) Reset() {
f.Name = ""
f.Value = ""
}
// String returns string representation of f.
func (f *Field) String() string {
name := f.Name
if name == "" {
name = "_msg"
}
return fmt.Sprintf("%q:%q", name, f.Value)
}
func (f *Field) marshal(dst []byte) []byte {
dst = encoding.MarshalBytes(dst, bytesutil.ToUnsafeBytes(f.Name))
dst = encoding.MarshalBytes(dst, bytesutil.ToUnsafeBytes(f.Value))
return dst
}
func (f *Field) unmarshal(src []byte) ([]byte, error) {
srcOrig := src
// Unmarshal field name
tail, b, err := encoding.UnmarshalBytes(src)
if err != nil {
return srcOrig, fmt.Errorf("cannot unmarshal field name: %w", err)
}
// Do not use bytesutil.InternBytes(b) here, since it works slower than the string(b) in prod
f.Name = string(b)
src = tail
// Unmarshal field value
tail, b, err = encoding.UnmarshalBytes(src)
if err != nil {
return srcOrig, fmt.Errorf("cannot unmarshal field value: %w", err)
}
// Do not use bytesutil.InternBytes(b) here, since it works slower than the string(b) in prod
f.Value = string(b)
src = tail
return src, nil
}
// rows is an aux structure used during rows merge
type rows struct {
fieldsBuf []Field
timestamps []int64
rows [][]Field
}
// reset resets rs
func (rs *rows) reset() {
fb := rs.fieldsBuf
for i := range fb {
fb[i].Reset()
}
rs.fieldsBuf = fb[:0]
rs.timestamps = rs.timestamps[:0]
rows := rs.rows
for i := range rows {
rows[i] = nil
}
rs.rows = rows[:0]
}
// appendRows appends rows with the given timestamps to rs.
func (rs *rows) appendRows(timestamps []int64, rows [][]Field) {
rs.timestamps = append(rs.timestamps, timestamps...)
fieldsBuf := rs.fieldsBuf
for _, fields := range rows {
fieldsLen := len(fieldsBuf)
fieldsBuf = append(fieldsBuf, fields...)
rs.rows = append(rs.rows, fieldsBuf[fieldsLen:])
}
rs.fieldsBuf = fieldsBuf
}
// mergeRows merges the args and appends them to rs.
func (rs *rows) mergeRows(timestampsA, timestampsB []int64, fieldsA, fieldsB [][]Field) {
for len(timestampsA) > 0 && len(timestampsB) > 0 {
i := 0
minTimestamp := timestampsB[0]
for i < len(timestampsA) && timestampsA[i] <= minTimestamp {
i++
}
rs.appendRows(timestampsA[:i], fieldsA[:i])
fieldsA = fieldsA[i:]
timestampsA = timestampsA[i:]
fieldsA, fieldsB = fieldsB, fieldsA
timestampsA, timestampsB = timestampsB, timestampsA
}
if len(timestampsA) == 0 {
rs.appendRows(timestampsB, fieldsB)
} else {
rs.appendRows(timestampsA, fieldsA)
}
}