.

wcfs/wcfs.go

@@ -257,10 +257,10 @@ package main
 // 2) head/bigfile/* of all bigfiles represent state as of zhead.At .
 // 3) for head/bigfile/* the following invariant is maintained:
 //
-//	#blk ∈ OS file cache    =>    ZBlk(#blk) + all BTree/Bucket that lead to it  ∈ zhead cache(%)
-//	                              (ZBlk* in ghost state)
+//	#blk ∈ OS file cache	=>  ZBlk(#blk) + all BTree/Bucket that lead to it  ∈ zhead live cache(%)
+//	                            (ZBlk* in ghost state)
 //
-//	                        =>    all BTree/Bucket that lead to blk are tracked (XXX)
+//	                        =>  all BTree/Bucket that lead to blk are tracked (XXX)
 //
 //    The invariant helps on invalidation: if we see a changed oid, and
 //    zhead.cache.lookup(oid) = ø -> we know we don't have to invalidate OS
@@ -848,22 +848,24 @@ retry:
 
 	// invalidate kernel cache for data in changed files
 	// NOTE no δFmu lock needed because zhead is WLocked
-	δF := bfdir.δFtail.Update(δZ, zhead)
 
-	if false {
-	fmt.Printf("\n\nS: handleδZ: δF (#%d):\n", len(δF.ByFile))
-	for file, δfile := range δF.ByFile {
-		blkv := δfile.Blocks.Elements()
-		sort.Slice(blkv, func(i, j int) bool {
-			return blkv[i] < blkv[j]
-		})
-		size := " "
-		if δfile.Size {
-			size = "S"
+	δF := bfdir.δFtail.Update(δZ, zhead) // δF <- δZ |tracked
+
+	if false { // XXX -> V(2) ?
+		// debug dump δF
+		fmt.Printf("\n\nS: handleδZ: δF (#%d):\n", len(δF.ByFile))
+		for file, δfile := range δF.ByFile {
+			blkv := δfile.Blocks.Elements()
+			sort.Slice(blkv, func(i, j int) bool {
+				return blkv[i] < blkv[j]
+			})
+			size := " "
+			if δfile.Size {
+				size = "S"
+			}
+			fmt.Printf("S: \t- %s\t%s %v\n", file.zfile.POid(), size, blkv)
 		}
-		fmt.Printf("S: \t- %s\t%s %v\n", file.zfile.POid(), size, blkv)
-	}
-	fmt.Printf("\n\n")
+		fmt.Printf("\n\n")
 	}
 
 	wg := xsync.NewWorkGroup(ctx)
@@ -876,7 +878,7 @@ retry:
 		for blk := range δfile.Blocks {
 			blk := blk
 			wg.Go(func(ctx context.Context) error {
-				return file.invalidateBlk(ctx, blk) // XXX +ctx ?
+				return file.invalidateBlk(ctx, blk)
 			})
 		}
 	}
@@ -1472,7 +1474,9 @@ func (f *BigFile) readPinWatchers(ctx context.Context, blk int64, treepath []btr
 
 //	fmt.Printf("S: read #%d -> pin watchers (#%d)\n", blk, len(f.watchTab))
 
-	// update δFtail index
+	// update δFtail index	XXX -> move upper into readBlk ?
+	// (δFtail is just for δZ -> δF invalidation handling and is needed without isolation protocol)
+	// XXX ^^^ no - also need to query to send pins
 	bfdir := f.head.bfdir
 	bfdir.δFmu.Lock()		// XXX locking correct? XXX -> better push down?
 	bfdir.δFtail.Track(f, blk, treepath, zblk)	// XXX pass in zblk.rev here?

wcfs/zblk.go

@@ -459,7 +459,7 @@ func (bf *zBigFileState) PySetState(pystate interface{}) (err error) {
 //
 // it also returns:
 //
-//	- BTree path in .blktab for loaded block,
+//	- BTree path in .blktab to loaded block,
 //	- max(_.serial for _ in ZBlk(#blk), all BTree/Bucket that lead to ZBlk)
 //	  which provides a rough upper-bound estimate for file[blk] revision.
 //

wcfs/δftail.go

@@ -428,6 +428,7 @@ func (δFtail *ΔFtail) SliceByFileRev(file *BigFile, lo, hi zodb.Tid) /*readonl
 
 }
 
+// XXX -> ΔFtail.BlkRevAt (meth of ΔFtail, not file)
 // XXX -> BlkRevAt
 // LastBlkRev returns last revision that changed file[blk] as of @at database state.
 //