// cursor will combine the in memory cache and flush cache (if a flush is currently happening) to give a single ordered cursor for the key
func (p *Partition) cursor(series string, fields []string, dec *tsdb.FieldCodec, ascending bool) *cursor {
p.mu.Lock()
defer p.mu.Unlock()
entry := p.cache[series]
if entry == nil {
entry = &cacheEntry{}
}
// if we're in the middle of a flush, combine the previous cache
// with this one for the cursor
if p.flushCache != nil {
if fc, ok := p.flushCache[series]; ok {
c := make([][]byte, len(fc), len(fc)+len(entry.points))
copy(c, fc)
c = append(c, entry.points...)
dedupe := tsdb.DedupeEntries(c)
return newCursor(dedupe, fields, dec, ascending)
}
}
if entry.isDirtySort {
entry.points = tsdb.DedupeEntries(entry.points)
entry.isDirtySort = false
}
// Build a copy so modifications to the partition don't change the result set
a := make([][]byte, len(entry.points))
copy(a, entry.points)
return newCursor(a, fields, dec, ascending)
}
// cursor will combine the in memory cache and flush cache (if a flush is currently happening) to give a single ordered cursor for the key
func (p *Partition) cursor(key string) *cursor {
p.mu.Lock()
defer p.mu.Unlock()
entry := p.cache[key]
if entry == nil {
entry = &cacheEntry{}
}
// if we're in the middle of a flush, combine the previous cache
// with this one for the cursor
if p.flushCache != nil {
if fc, ok := p.flushCache[key]; ok {
c := make([][]byte, len(fc), len(fc)+len(entry.points))
copy(c, fc)
c = append(c, entry.points...)
dedupe := tsdb.DedupeEntries(c)
return &cursor{cache: dedupe}
}
}
if entry.isDirtySort {
entry.points = tsdb.DedupeEntries(entry.points)
entry.isDirtySort = false
}
// build a copy so modifications to the partition don't change the result set
a := make([][]byte, len(entry.points))
copy(a, entry.points)
return &cursor{cache: a}
}
// cursor will combine the in memory cache and flush cache (if a flush is currently happening) to give a single ordered cursor for the key
func (p *Partition) cursor(key string) *cursor {
p.mu.Lock()
defer p.mu.Unlock()
entry := p.cache[key]
if entry == nil {
return &cursor{}
}
// if we're in the middle of a flush, combine the previous cache
// with this one for the cursor
if p.flushCache != nil {
if fc, ok := p.flushCache[key]; ok {
c := make([][]byte, len(fc), len(fc)+len(entry.points))
copy(c, fc)
c = append(c, entry.points...)
return &cursor{cache: tsdb.DedupeEntries(c)}
}
}
if entry.isDirtySort {
entry.points = tsdb.DedupeEntries(entry.points)
entry.isDirtySort = false
}
return &cursor{cache: entry.points}
}
// MergePoints returns a map of all points merged together by key.
// Later points will overwrite earlier ones.
func MergePoints(a []Points) Points {
// Combine all points into one set.
m := make(Points)
for _, set := range a {
for key, values := range set {
m[key] = append(m[key], values...)
}
}
// Dedupe points.
for key, values := range m {
m[key] = tsdb.DedupeEntries(values)
}
return m
}
// writeIndex writes a set of points for a single key.
func (e *Engine) writeIndex(tx *bolt.Tx, key string, a [][]byte) error {
// Ignore if there are no points.
if len(a) == 0 {
return nil
}
e.statMap.Add(statPointsWrite, int64(len(a)))
// Create or retrieve series bucket.
bkt, err := tx.Bucket([]byte("points")).CreateBucketIfNotExists([]byte(key))
if err != nil {
return fmt.Errorf("create series bucket: %s", err)
}
c := bkt.Cursor()
// Ensure the slice is sorted before retrieving the time range.
a = tsdb.DedupeEntries(a)
e.statMap.Add(statPointsWriteDedupe, int64(len(a)))
// Convert the raw time and byte slices to entries with lengths
for i, p := range a {
timestamp := int64(btou64(p[0:8]))
a[i] = MarshalEntry(timestamp, p[8:])
}
// Determine time range of new data.
tmin, tmax := int64(btou64(a[0][0:8])), int64(btou64(a[len(a)-1][0:8]))
// If tmin is after the last block then append new blocks.
//
// This is the optimized fast path. Otherwise we need to merge the points
// with existing blocks on disk and rewrite all the blocks for that range.
if k, v := c.Last(); k == nil {
bkt.FillPercent = 1.0
if err := e.writeBlocks(bkt, a); err != nil {
return fmt.Errorf("new blocks: %s", err)
}
return nil
} else {
// Determine uncompressed block size.
sz, err := snappy.DecodedLen(v[8:])
if err != nil {
return fmt.Errorf("snappy decoded len: %s", err)
}
// Append new blocks if our time range is past the last on-disk time
// and if our previous block was at least the minimum block size.
if int64(btou64(v[0:8])) < tmin && sz >= e.BlockSize {
bkt.FillPercent = 1.0
if err := e.writeBlocks(bkt, a); err != nil {
return fmt.Errorf("append blocks: %s", err)
}
return nil
}
// Otherwise fallthrough to slower insert mode.
e.statMap.Add(statSlowInsert, 1)
}
// Generate map of inserted keys.
m := make(map[int64]struct{})
for _, b := range a {
m[int64(btou64(b[0:8]))] = struct{}{}
}
// If time range overlaps existing blocks then unpack full range and reinsert.
var existing [][]byte
for k, v := c.First(); k != nil; k, v = c.Next() {
// Determine block range.
bmin, bmax := int64(btou64(k)), int64(btou64(v[0:8]))
// Skip over all blocks before the time range.
// Exit once we reach a block that is beyond our time range.
if bmax < tmin {
continue
} else if bmin > tmax {
break
}
// Decode block.
buf, err := snappy.Decode(nil, v[8:])
if err != nil {
return fmt.Errorf("decode block: %s", err)
}
// Copy out any entries that aren't being overwritten.
for _, entry := range SplitEntries(buf) {
if _, ok := m[int64(btou64(entry[0:8]))]; !ok {
existing = append(existing, entry)
}
}
// Delete block in database.
c.Delete()
}
// Merge entries before rewriting.
a = append(existing, a...)
sort.Sort(tsdb.ByteSlices(a))
// Rewrite points to new blocks.
if err := e.writeBlocks(bkt, a); err != nil {
return fmt.Errorf("rewrite blocks: %s", err)
}
return nil
}
