core/rawdb: swap tailId and itemOffset for deleted items in freezer (#21220)

* fix(freezer): tailId filenum offset were misplaced

* core/rawdb: assume first item in freezer always start from zero
This commit is contained in:
zhangsoledad 2020-06-17 15:41:07 +08:00 committed by GitHub
parent eb9d7d15ec
commit bcf19bc4be
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 55 additions and 16 deletions

View File

@ -232,8 +232,8 @@ func (t *freezerTable) repair() error {
t.index.ReadAt(buffer, 0)
firstIndex.unmarshalBinary(buffer)
t.tailId = firstIndex.offset
t.itemOffset = firstIndex.filenum
t.tailId = firstIndex.filenum
t.itemOffset = firstIndex.offset
t.index.ReadAt(buffer, offsetsSize-indexEntrySize)
lastIndex.unmarshalBinary(buffer)
@ -519,16 +519,27 @@ func (t *freezerTable) Append(item uint64, blob []byte) error {
// getBounds returns the indexes for the item
// returns start, end, filenumber and error
func (t *freezerTable) getBounds(item uint64) (uint32, uint32, uint32, error) {
var startIdx, endIdx indexEntry
buffer := make([]byte, indexEntrySize)
if _, err := t.index.ReadAt(buffer, int64(item*indexEntrySize)); err != nil {
return 0, 0, 0, err
}
startIdx.unmarshalBinary(buffer)
var startIdx, endIdx indexEntry
// Read second index
if _, err := t.index.ReadAt(buffer, int64((item+1)*indexEntrySize)); err != nil {
return 0, 0, 0, err
}
endIdx.unmarshalBinary(buffer)
// Read first index (unless it's the very first item)
if item != 0 {
if _, err := t.index.ReadAt(buffer, int64(item*indexEntrySize)); err != nil {
return 0, 0, 0, err
}
startIdx.unmarshalBinary(buffer)
} else {
// Special case if we're reading the first item in the freezer. We assume that
// the first item always start from zero(regarding the deletion, we
// only support deletion by files, so that the assumption is held).
// This means we can use the first item metadata to carry information about
// the 'global' offset, for the deletion-case
return 0, endIdx.offset, endIdx.filenum, nil
}
if startIdx.filenum != endIdx.filenum {
// If a piece of data 'crosses' a data-file,
// it's actually in one piece on the second data-file.

View File

@ -552,8 +552,8 @@ func TestOffset(t *testing.T) {
tailId := uint32(2) // First file is 2
itemOffset := uint32(4) // We have removed four items
zeroIndex := indexEntry{
offset: tailId,
filenum: itemOffset,
filenum: tailId,
offset: itemOffset,
}
buf := zeroIndex.marshallBinary()
// Overwrite index zero
@ -567,39 +567,67 @@ func TestOffset(t *testing.T) {
}
// Now open again
{
checkPresent := func(numDeleted uint64) {
f, err := newCustomTable(os.TempDir(), fname, rm, wm, sg, 40, true)
if err != nil {
t.Fatal(err)
}
f.printIndex()
// It should allow writing item 6
f.Append(6, getChunk(20, 0x99))
f.Append(numDeleted+2, getChunk(20, 0x99))
// It should be fine to fetch 4,5,6
if got, err := f.Retrieve(4); err != nil {
if got, err := f.Retrieve(numDeleted); err != nil {
t.Fatal(err)
} else if exp := getChunk(20, 0xbb); !bytes.Equal(got, exp) {
t.Fatalf("expected %x got %x", exp, got)
}
if got, err := f.Retrieve(5); err != nil {
if got, err := f.Retrieve(numDeleted + 1); err != nil {
t.Fatal(err)
} else if exp := getChunk(20, 0xaa); !bytes.Equal(got, exp) {
t.Fatalf("expected %x got %x", exp, got)
}
if got, err := f.Retrieve(6); err != nil {
if got, err := f.Retrieve(numDeleted + 2); err != nil {
t.Fatal(err)
} else if exp := getChunk(20, 0x99); !bytes.Equal(got, exp) {
t.Fatalf("expected %x got %x", exp, got)
}
// It should error at 0, 1,2,3
for i := 0; i < 4; i++ {
if _, err := f.Retrieve(uint64(i)); err == nil {
for i := numDeleted - 1; i > numDeleted-10; i-- {
if _, err := f.Retrieve(i); err == nil {
t.Fatal("expected err")
}
}
}
checkPresent(4)
// Now, let's pretend we have deleted 1M items
{
// Read the index file
p := filepath.Join(os.TempDir(), fmt.Sprintf("%v.ridx", fname))
indexFile, err := os.OpenFile(p, os.O_RDWR, 0644)
if err != nil {
t.Fatal(err)
}
indexBuf := make([]byte, 3*indexEntrySize)
indexFile.Read(indexBuf)
// Update the index file, so that we store
// [ file = 2, offset = 1M ] at index zero
tailId := uint32(2) // First file is 2
itemOffset := uint32(1000000) // We have removed 1M items
zeroIndex := indexEntry{
offset: itemOffset,
filenum: tailId,
}
buf := zeroIndex.marshallBinary()
// Overwrite index zero
copy(indexBuf, buf)
indexFile.WriteAt(indexBuf, 0)
indexFile.Close()
}
checkPresent(1000000)
}
// TODO (?)