seaweedfs/weed/filer/filechunk_section.go
2023-01-10 01:35:44 -08:00

135 lines
3.8 KiB
Go

package filer
import (
"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
"sync"
)
const SectionSize = 2 * 1024 * 1024 * 32 // 64MiB
type SectionIndex int64
type FileChunkSection struct {
sectionIndex SectionIndex
chunks []*filer_pb.FileChunk
visibleIntervals *IntervalList[*VisibleInterval]
chunkViews *IntervalList[*ChunkView]
reader *ChunkReadAt
lock sync.Mutex
}
func NewFileChunkSection(si SectionIndex) *FileChunkSection {
return &FileChunkSection{
sectionIndex: si,
}
}
func (section *FileChunkSection) addChunk(chunk *filer_pb.FileChunk) error {
section.lock.Lock()
defer section.lock.Unlock()
start, stop := max(int64(section.sectionIndex)*SectionSize, chunk.Offset), min(((int64(section.sectionIndex)+1)*SectionSize), chunk.Offset+int64(chunk.Size))
section.chunks = append(section.chunks, chunk)
if section.visibleIntervals == nil {
section.visibleIntervals = readResolvedChunks(section.chunks, int64(section.sectionIndex)*SectionSize, (int64(section.sectionIndex)+1)*SectionSize)
} else {
MergeIntoVisibles(section.visibleIntervals, start, stop, chunk)
garbageFileIds := FindGarbageChunks(section.visibleIntervals, start, stop)
removeGarbageChunks(section, garbageFileIds)
}
if section.chunkViews != nil {
MergeIntoChunkViews(section.chunkViews, start, stop, chunk)
}
return nil
}
func removeGarbageChunks(section *FileChunkSection, garbageFileIds map[string]struct{}) {
for i := 0; i < len(section.chunks); {
t := section.chunks[i]
length := len(section.chunks)
if _, found := garbageFileIds[t.FileId]; found {
if i < length-1 {
section.chunks[i] = section.chunks[length-1]
}
section.chunks = section.chunks[:length-1]
} else {
i++
}
}
}
func (section *FileChunkSection) setupForRead(group *ChunkGroup, fileSize int64) {
if section.visibleIntervals == nil {
section.visibleIntervals = readResolvedChunks(section.chunks, int64(section.sectionIndex)*SectionSize, (int64(section.sectionIndex)+1)*SectionSize)
section.chunks, _ = SeparateGarbageChunks(section.visibleIntervals, section.chunks)
if section.reader != nil {
_ = section.reader.Close()
section.reader = nil
}
}
if section.chunkViews == nil {
section.chunkViews = ViewFromVisibleIntervals(section.visibleIntervals, int64(section.sectionIndex)*SectionSize, (int64(section.sectionIndex)+1)*SectionSize)
}
if section.reader == nil {
section.reader = NewChunkReaderAtFromClient(group.lookupFn, section.chunkViews, group.chunkCache, min(int64(section.sectionIndex+1)*SectionSize, fileSize))
}
section.reader.fileSize = fileSize
}
func (section *FileChunkSection) readDataAt(group *ChunkGroup, fileSize int64, buff []byte, offset int64) (n int, tsNs int64, err error) {
section.lock.Lock()
defer section.lock.Unlock()
section.setupForRead(group, fileSize)
return section.reader.ReadAtWithTime(buff, offset)
}
func (section *FileChunkSection) DataStartOffset(group *ChunkGroup, offset int64, fileSize int64) int64 {
section.lock.Lock()
defer section.lock.Unlock()
section.setupForRead(group, fileSize)
for x := section.visibleIntervals.Front(); x != nil; x = x.Next {
visible := x.Value
if visible.stop <= offset {
continue
}
if offset < visible.start {
return offset
}
return offset
}
return -1
}
func (section *FileChunkSection) NextStopOffset(group *ChunkGroup, offset int64, fileSize int64) int64 {
section.lock.Lock()
defer section.lock.Unlock()
section.setupForRead(group, fileSize)
isAfterOffset := false
for x := section.visibleIntervals.Front(); x != nil; x = x.Next {
visible := x.Value
if !isAfterOffset {
if visible.stop <= offset {
continue
}
isAfterOffset = true
}
if offset < visible.start {
return offset
}
// now visible.start <= offset
if offset < visible.stop {
offset = visible.stop
}
}
return offset
}