more solid weed mount (#4089)

* compare chunks by timestamp

* fix slab clearing error

* fix test compilation

* move oldest chunk to sealed, instead of by fullness

* lock on fh.entryViewCache

* remove verbose logs

* revert slat clearing

* less logs

* less logs

* track write and read by timestamp

* remove useless logic

* add entry lock on file handle release

* use mem chunk only, swap file chunk has problems

* comment out code that maybe used later

* add debug mode to compare data read and write

* more efficient readResolvedChunks with linked list

* small optimization

* fix test compilation

* minor fix on writer

* add SeparateGarbageChunks

* group chunks into sections

* turn off debug mode

* fix tests

* fix tests

* tmp enable swap file chunk

* Revert "tmp enable swap file chunk"

This reverts commit 985137ec472924e4815f258189f6ca9f2168a0a7.

* simple refactoring

* simple refactoring

* do not re-use swap file chunk. Sealed chunks should not be re-used.

* comment out debugging facilities

* either mem chunk or swap file chunk is fine now

* remove orderedMutex  as *semaphore.Weighted

not found impactful

* optimize size calculation for changing large files

* optimize performance to avoid going through the long list of chunks

* still problems with swap file chunk

* rename

* tiny optimization

* swap file chunk save only successfully read data

* fix

* enable both mem and swap file chunk

* resolve chunks with range

* rename

* fix chunk interval list

* also change file handle chunk group when adding chunks

* pick in-active chunk with time-decayed counter

* fix compilation

* avoid nil with empty fh.entry

* refactoring

* rename

* rename

* refactor visible intervals to *list.List

* refactor chunkViews to *list.List

* add IntervalList for generic interval list

* change visible interval to use IntervalList in generics

* cahnge chunkViews to *IntervalList[*ChunkView]

* use NewFileChunkSection to create

* rename variables

* refactor

* fix renaming leftover

* renaming

* renaming

* add insert interval

* interval list adds lock

* incrementally add chunks to readers

Fixes:
1. set start and stop offset for the value object
2. clone the value object
3. use pointer instead of copy-by-value when passing to interval.Value
4. use insert interval since adding chunk could be out of order

* fix tests compilation

* fix tests compilation

1 files changed, 119 insertions, 0 deletions

diff --git a/weed/filer/filechunk_section.go b/weed/filer/filechunk_section.go
new file mode 100644
index 000000000..60c919569
--- /dev/null
+++ b/weed/filer/filechunk_section.go
@@ -0,0 +1,119 @@
+package filer
+
+import (
+	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
+	"sync"
+)
+
+const SectionSize = 2 * 1024 * 1024 * 128 // 256MiB
+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 {
+		MergeIntoVisibles(section.visibleIntervals, start, stop, chunk)
+	}
+
+	if section.visibleIntervals != nil {
+		section.chunks, _ = SeparateGarbageChunks(section.visibleIntervals, section.chunks)
+	}
+
+	if section.chunkViews != nil {
+		MergeIntoChunkViews(section.chunkViews, start, stop, chunk)
+	}
+
+	return nil
+}
+
+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
+}