meta: in compaction improve the method of skipsome

pkg/meta/base_test.go

@@ -1548,8 +1548,8 @@ func testCompaction(t *testing.T, m Meta, trash bool) {
 	if st := m.Read(ctx, inode, 0, &slices); st != 0 {
 		t.Fatalf("read 0: %s", st)
 	}
-	if len(slices) != 1 || slices[0].Len != 3<<20 {
-		t.Fatalf("inode %d should be compacted, but have %d slices, size %d", inode, len(slices), slices[0].Len)
+	if len(slices) != 2 {
+		t.Fatalf("inode %d should be compacted, but have %d slices, size %d: %+v", inode, len(slices), slices[0].Len, slices)
 	}
 
 	m.NewSlice(ctx, &sliceId)
@@ -1567,9 +1567,23 @@ func testCompaction(t *testing.T, m Meta, trash bool) {
 		t.Fatalf("read 1: %s", st)
 	}
 	// compact twice: 4515328+2607724-2338508 = 4784544; 8829056+1074933-2338508-4784544=2780937
-	if len(slices) != 3 || slices[0].Len != 2338508 || slices[1].Len != 4784544 || slices[2].Len != 2780937 {
-		t.Fatalf("inode %d should be compacted, but have %d slices, size %d,%d,%d",
-			inode, len(slices), slices[0].Len, slices[1].Len, slices[2].Len)
+	if len(slices) != 1 {
+		t.Fatalf("inode %d should be compacted, but have %d slices: %+v", inode, len(slices), slices)
+	}
+
+	m.NewSlice(ctx, &sliceId)
+	_ = m.Write(ctx, inode, 3, 0, Slice{Id: sliceId, Size: 2338508, Len: 2338508}, time.Now())
+	_ = m.CopyFileRange(ctx, inode, 3*ChunkSize, inode, 4*ChunkSize, 2338508, 0, nil, nil)
+	_ = m.Fallocate(ctx, inode, fallocZeroRange, 4*ChunkSize, ChunkSize, nil)
+	_ = m.CopyFileRange(ctx, inode, 3*ChunkSize, inode, 4*ChunkSize, 2338508, 0, nil, nil)
+	if c, ok := m.(compactor); ok {
+		c.compactChunk(inode, 4, false, true)
+	}
+	if st := m.Read(ctx, inode, 4, &slices); st != 0 {
+		t.Fatalf("read inode %d chunk 4: %s", inode, st)
+	}
+	if len(slices) != 1 || slices[0].Len != 2338508 {
+		t.Fatalf("inode %d should be compacted, but have %d slices, size %d", inode, len(slices), slices[0].Len)
 	}
 }
 

pkg/meta/slice.go

@@ -183,21 +183,14 @@ func compactChunk(ss []*slice) (uint32, uint32, []Slice) {
 func skipSome(chunk []*slice) int {
 	var skipped int
 	var total = len(chunk)
+	_, size, _ := compactChunk(chunk)
 	for skipped < total {
-		ss := chunk[skipped:]
-		pos, size, c := compactChunk(ss)
-		first := ss[0]
-		if first.len < (1<<20) || first.len*5 < size || size == 0 {
-			// it's too small
-			break
-		}
-		isFirst := func(pos uint32, s Slice) bool {
-			return pos == first.pos && s.Id == first.id && s.Off == first.off && s.Len == first.len
-		}
-		if !isFirst(pos, c[0]) {
-			// it's not the first slice, compact it
+		_, size1, _ := compactChunk(chunk[skipped+1:])
+		reduced := size - size1
+		if size1 == 0 || reduced < chunk[skipped].len || reduced*5 < size || reduced < 2<<20 {
 			break
 		}
+		size = size1
 		skipped++
 	}
 	return skipped