block manager: fix bug where rebalance didn't delete old copies
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This commit is contained in:
Alex 2023-09-07 16:04:03 +02:00
parent 2657b5c1b9
commit be91ef6294
3 changed files with 59 additions and 18 deletions

View file

@ -21,6 +21,7 @@ pub enum DataBlock {
Compressed(Bytes),
}
#[derive(Debug)]
pub enum DataBlockPath {
/// Uncompressed data fail
Plain(PathBuf),

View file

@ -645,6 +645,19 @@ impl BlockManager {
None
}
/// Rewrite a block at the primary location for its path and delete the old path.
/// Returns the number of bytes read/written
pub(crate) async fn fix_block_location(
&self,
hash: &Hash,
wrong_path: DataBlockPath,
) -> Result<usize, Error> {
self.lock_mutate(hash)
.await
.fix_block_location(hash, wrong_path, self)
.await
}
async fn lock_mutate(&self, hash: &Hash) -> MutexGuard<'_, BlockManagerLocked> {
let tracer = opentelemetry::global::tracer("garage");
let ilock = u16::from_be_bytes([hash.as_slice()[0], hash.as_slice()[1]]) as usize
@ -682,6 +695,17 @@ impl BlockManagerLocked {
hash: &Hash,
data: &DataBlock,
mgr: &BlockManager,
) -> Result<(), Error> {
let existing_path = mgr.find_block(hash).await;
self.write_block_inner(hash, data, mgr, existing_path).await
}
async fn write_block_inner(
&self,
hash: &Hash,
data: &DataBlock,
mgr: &BlockManager,
existing_path: Option<DataBlockPath>,
) -> Result<(), Error> {
let compressed = data.is_compressed();
let data = data.inner_buffer();
@ -694,7 +718,7 @@ impl BlockManagerLocked {
tgt_path.set_extension("zst");
}
let to_delete = match (mgr.find_block(hash).await, compressed) {
let to_delete = match (existing_path, compressed) {
// If the block is stored in the wrong directory,
// write it again at the correct path and delete the old path
(Some(DataBlockPath::Plain(p)), false) if p != tgt_path => Some(p),
@ -716,6 +740,7 @@ impl BlockManagerLocked {
// If the block isn't stored already, just store what is given to us
(None, _) => None,
};
assert!(to_delete.as_ref() != Some(&tgt_path));
let mut path_tmp = tgt_path.clone();
let tmp_extension = format!("tmp{}", hex::encode(thread_rng().gen::<[u8; 4]>()));
@ -792,6 +817,18 @@ impl BlockManagerLocked {
}
Ok(())
}
async fn fix_block_location(
&self,
hash: &Hash,
wrong_path: DataBlockPath,
mgr: &BlockManager,
) -> Result<usize, Error> {
let data = mgr.read_block_from(hash, &wrong_path).await?;
self.write_block_inner(hash, &data, mgr, Some(wrong_path))
.await?;
Ok(data.inner_buffer().len())
}
}
async fn read_stream_to_end(mut stream: ByteStream) -> Result<Bytes, Error> {

View file

@ -558,17 +558,21 @@ impl Worker for RebalanceWorker {
fn status(&self) -> WorkerStatus {
let t_cur = self.t_finished.unwrap_or_else(|| now_msec());
let rate = self.moved_bytes / std::cmp::max(1, (t_cur - self.t_started) / 1000);
let mut freeform = vec![
format!("Blocks moved: {}", self.moved),
format!(
"Bytes moved: {} ({}/s)",
bytesize::ByteSize::b(self.moved_bytes),
bytesize::ByteSize::b(rate)
),
format!("Started: {}", msec_to_rfc3339(self.t_started)),
];
if let Some(t_fin) = self.t_finished {
freeform.push(format!("Finished: {}", msec_to_rfc3339(t_fin)))
}
WorkerStatus {
progress: Some(format!("{:.2}%", self.block_iter.progress() * 100.)),
freeform: vec![
format!("Blocks moved: {}", self.moved),
format!(
"Bytes moved: {} ({}/s)",
bytesize::ByteSize::b(self.moved_bytes),
bytesize::ByteSize::b(rate)
),
format!("Started: {}", msec_to_rfc3339(self.t_started)),
],
freeform,
..Default::default()
}
}
@ -576,10 +580,10 @@ impl Worker for RebalanceWorker {
async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
if let Some((path, hash)) = self.block_iter.next().await? {
let prim_loc = self.manager.data_layout.load().primary_block_dir(&hash);
if path.parent().expect("no parent?") != prim_loc {
let path = match path.extension() {
None => DataBlockPath::Plain(path),
Some(x) if x.to_str() == Some("zst") => DataBlockPath::Compressed(path),
if path.ancestors().all(|x| x != prim_loc) {
let block_path = match path.extension() {
None => DataBlockPath::Plain(path.clone()),
Some(x) if x.to_str() == Some("zst") => DataBlockPath::Compressed(path.clone()),
_ => {
warn!("not rebalancing file: {}", path.to_string_lossy());
return Ok(WorkerState::Busy);
@ -587,11 +591,10 @@ impl Worker for RebalanceWorker {
};
// block is not in its primary location,
// move it there (reading and re-writing does the trick)
debug!("rebalance: moving block {:?}", hash);
let data = self.manager.read_block_from(&hash, &path).await?;
self.manager.write_block(&hash, &data).await?;
debug!("rebalance: moving block {:?} => {:?}", block_path, prim_loc);
let block_len = self.manager.fix_block_location(&hash, block_path).await?;
self.moved += 1;
self.moved_bytes += data.inner_buffer().len() as u64;
self.moved_bytes += block_len as u64;
}
Ok(WorkerState::Busy)
} else {