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

weed/mount/page_writer/upload_pipeline.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"github.com/seaweedfs/seaweedfs/weed/glog"
 	"github.com/seaweedfs/seaweedfs/weed/util"
+	"math"
 	"sync"
 	"sync/atomic"
 )
@@ -55,7 +56,8 @@ func NewUploadPipeline(writers *util.LimitedConcurrentExecutor, chunkSize int64,
 	return t
 }
 
-func (up *UploadPipeline) SaveDataAt(p []byte, off int64, isSequential bool) (n int) {
+func (up *UploadPipeline) SaveDataAt(p []byte, off int64, isSequential bool, tsNs int64) (n int) {
+
 	up.chunksLock.Lock()
 	defer up.chunksLock.Unlock()
 
@@ -65,33 +67,39 @@ func (up *UploadPipeline) SaveDataAt(p []byte, off int64, isSequential bool) (n
 	if !found {
 		if len(up.writableChunks) > up.writableChunkLimit {
 			// if current file chunks is over the per file buffer count limit
-			fullestChunkIndex, fullness := LogicChunkIndex(-1), int64(0)
-			for lci, mc := range up.writableChunks {
-				chunkFullness := mc.WrittenSize()
-				if fullness < chunkFullness {
-					fullestChunkIndex = lci
-					fullness = chunkFullness
+			laziestChunkIndex, lowestActivityScore := LogicChunkIndex(-1), int64(math.MaxInt64)
+			for wci, wc := range up.writableChunks {
+				activityScore := wc.ActivityScore()
+				if lowestActivityScore > activityScore {
+					laziestChunkIndex = wci
+					lowestActivityScore = activityScore
 				}
 			}
-			up.moveToSealed(up.writableChunks[fullestChunkIndex], fullestChunkIndex)
-			// fmt.Printf("flush chunk %d with %d bytes written\n", logicChunkIndex, fullness)
+			up.moveToSealed(up.writableChunks[laziestChunkIndex], laziestChunkIndex)
+			// fmt.Printf("flush chunk %d with %d bytes written\n", logicChunkIndex, oldestTs)
 		}
 		if isSequential &&
 			len(up.writableChunks) < up.writableChunkLimit &&
 			atomic.LoadInt64(&memChunkCounter) < 4*int64(up.writableChunkLimit) {
 			pageChunk = NewMemChunk(logicChunkIndex, up.ChunkSize)
 		} else {
-			pageChunk = up.swapFile.NewTempFileChunk(logicChunkIndex)
+			pageChunk = up.swapFile.NewSwapFileChunk(logicChunkIndex)
 		}
 		up.writableChunks[logicChunkIndex] = pageChunk
 	}
-	n = pageChunk.WriteDataAt(p, off)
+	//if _, foundSealed := up.sealedChunks[logicChunkIndex]; foundSealed {
+	//	println("found already sealed chunk", logicChunkIndex)
+	//}
+	//if _, foundReading := up.activeReadChunks[logicChunkIndex]; foundReading {
+	//	println("found active read chunk", logicChunkIndex)
+	//}
+	n = pageChunk.WriteDataAt(p, off, tsNs)
 	up.maybeMoveToSealed(pageChunk, logicChunkIndex)
 
 	return
 }
 
-func (up *UploadPipeline) MaybeReadDataAt(p []byte, off int64) (maxStop int64) {
+func (up *UploadPipeline) MaybeReadDataAt(p []byte, off int64, tsNs int64) (maxStop int64) {
 	logicChunkIndex := LogicChunkIndex(off / up.ChunkSize)
 
 	up.chunksLock.Lock()
@@ -103,12 +111,8 @@ func (up *UploadPipeline) MaybeReadDataAt(p []byte, off int64) (maxStop int64) {
 	// read from sealed chunks first
 	sealedChunk, found := up.sealedChunks[logicChunkIndex]
 	if found {
-		sealedChunk.referenceCounter++
-	}
-	if found {
-		maxStop = sealedChunk.chunk.ReadDataAt(p, off)
+		maxStop = sealedChunk.chunk.ReadDataAt(p, off, tsNs)
 		glog.V(4).Infof("%s read sealed memchunk [%d,%d)", up.filepath, off, maxStop)
-		sealedChunk.FreeReference(fmt.Sprintf("%s finish reading chunk %d", up.filepath, logicChunkIndex))
 	}
 
 	// read from writable chunks last
@@ -116,7 +120,7 @@ func (up *UploadPipeline) MaybeReadDataAt(p []byte, off int64) (maxStop int64) {
 	if !found {
 		return
 	}
-	writableMaxStop := writableChunk.ReadDataAt(p, off)
+	writableMaxStop := writableChunk.ReadDataAt(p, off, tsNs)
 	glog.V(4).Infof("%s read writable memchunk [%d,%d)", up.filepath, off, writableMaxStop)
 	maxStop = max(maxStop, writableMaxStop)