Deuxfleurs/garage
48
55
Fork 73
Code Issues 100 Pull requests 15 Releases 30 Wiki Activity

Fix a bug when a migration is followed by a rebalance #238

Merged
lx merged 1 commit from bug/migrate-rebalance into main 2022-02-10 16:38:28 +00:00
Conversation 0 Commits 1 Files changed 1 +18 -9
1 changed files with 18 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files
Showing only changes of commit d2c54abf8a - Show all commits

27
src/table/data.rs
View file

@ -130,22 +130,31 @@ where
let tree_key = self.tree_key(update.partition_key(), update.sort_key());
let changed = (&self.store, &self.merkle_todo).transaction(|(store, mkl_todo)| {
let (old_entry, new_entry) = match store.get(&tree_key)? {
Some(prev_bytes) => {
let (old_entry, old_bytes, new_entry) = match store.get(&tree_key)? {
Some(old_bytes) => {
let old_entry = self
.decode_entry(&prev_bytes)
.decode_entry(&old_bytes)
.map_err(sled::transaction::ConflictableTransactionError::Abort)?;
let mut new_entry = old_entry.clone();
new_entry.merge(&update);
(Some(old_entry), new_entry)
(Some(old_entry), Some(old_bytes), new_entry)
}
None => (None, update.clone()),
None => (None, None, update.clone()),
};
if Some(&new_entry) != old_entry.as_ref() {
let new_bytes = rmp_to_vec_all_named(&new_entry)
.map_err(Error::RmpEncode)
.map_err(sled::transaction::ConflictableTransactionError::Abort)?;
// Scenario 1: the value changed, so of course there is a change
let value_changed = Some(&new_entry) != old_entry.as_ref();
// Scenario 2: the value didn't change but due to a migration in the
// data format, the messagepack encoding changed. In this case
// we have to write the migrated value in the table and update
// the associated Merkle tree entry.
let new_bytes = rmp_to_vec_all_named(&new_entry)
.map_err(Error::RmpEncode)
.map_err(sled::transaction::ConflictableTransactionError::Abort)?;
let encoding_changed = Some(&new_bytes[..]) != old_bytes.as_ref().map(|x| &x[..]);
if value_changed || encoding_changed {
let new_bytes_hash = blake2sum(&new_bytes[..]);
mkl_todo.insert(tree_key.clone(), new_bytes_hash.as_slice())?;
store.insert(tree_key.clone(), new_bytes)?;