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use core::ops::Bound;
use std::sync::Arc;
use std::time::Duration;
use async_trait::async_trait;
use tokio::fs;
use tokio::sync::watch;
use garage_util::background::*;
use garage_util::data::*;
use garage_util::error::*;
use garage_util::tranquilizer::Tranquilizer;
use crate::manager::*;
pub struct RepairWorker {
manager: Arc<BlockManager>,
next_start: Option<Hash>,
block_iter: Option<BlockStoreIterator>,
}
impl RepairWorker {
pub fn new(manager: Arc<BlockManager>) -> Self {
Self {
manager,
next_start: None,
block_iter: None,
}
}
}
#[async_trait]
impl Worker for RepairWorker {
fn name(&self) -> String {
"Block repair worker".into()
}
async fn work(
&mut self,
_must_exit: &mut watch::Receiver<bool>,
) -> Result<WorkerStatus, Error> {
match self.block_iter.as_mut() {
None => {
// Phase 1: Repair blocks from RC table.
// We have to do this complicated two-step process where we first read a bunch
// of hashes from the RC table, and then insert them in the to-resync queue,
// because of SQLite. Basically, as long as we have an iterator on a DB table,
// we can't do anything else on the DB. The naive approach (which we had previously)
// of just iterating on the RC table and inserting items one to one in the resync
// queue can't work here, it would just provoke a deadlock in the SQLite adapter code.
// This is mostly because the Rust bindings for SQLite assume a worst-case scenario
// where SQLite is not compiled in thread-safe mode, so we have to wrap everything
// in a mutex (see db/sqlite_adapter.rs and discussion in PR #322).
let mut batch_of_hashes = vec![];
let start_bound = match self.next_start.as_ref() {
None => Bound::Unbounded,
Some(x) => Bound::Excluded(x.as_slice()),
};
for entry in self
.manager
.rc
.rc
.range::<&[u8], _>((start_bound, Bound::Unbounded))?
{
let (hash, _) = entry?;
let hash = Hash::try_from(&hash[..]).unwrap();
batch_of_hashes.push(hash);
if batch_of_hashes.len() >= 1000 {
break;
}
}
if batch_of_hashes.is_empty() {
// move on to phase 2
self.block_iter = Some(BlockStoreIterator::new(&self.manager).await?);
return Ok(WorkerStatus::Busy);
}
for hash in batch_of_hashes.into_iter() {
self.manager.put_to_resync(&hash, Duration::from_secs(0))?;
self.next_start = Some(hash)
}
Ok(WorkerStatus::Busy)
}
Some(bi) => {
// Phase 2: Repair blocks actually on disk
// Lists all blocks on disk and adds them to the resync queue.
// This allows us to find blocks we are storing but don't actually need,
// so that we can offload them if necessary and then delete them locally.
if let Some(hash) = bi.next().await? {
self.manager.put_to_resync(&hash, Duration::from_secs(0))?;
Ok(WorkerStatus::Busy)
} else {
Ok(WorkerStatus::Done)
}
}
}
}
async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerStatus {
unreachable!()
}
}
// ----
pub struct ScrubWorker {
manager: Arc<BlockManager>,
iterator: BlockStoreIterator,
tranquilizer: Tranquilizer,
tranquility: u32,
}
impl ScrubWorker {
pub async fn new(manager: Arc<BlockManager>, tranquility: u32) -> Result<Self, Error> {
let iterator = BlockStoreIterator::new(&manager).await?;
Ok(Self {
manager,
iterator,
tranquilizer: Tranquilizer::new(30),
tranquility,
})
}
}
#[async_trait]
impl Worker for ScrubWorker {
fn name(&self) -> String {
"Block scrub worker".into()
}
async fn work(
&mut self,
_must_exit: &mut watch::Receiver<bool>,
) -> Result<WorkerStatus, Error> {
self.tranquilizer.reset();
if let Some(hash) = self.iterator.next().await? {
let _ = self.manager.read_block(&hash).await;
Ok(self.tranquilizer.tranquilize_worker(self.tranquility))
} else {
Ok(WorkerStatus::Done)
}
}
async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerStatus {
unreachable!()
}
}
// ----
struct BlockStoreIterator {
path: Vec<fs::ReadDir>,
}
impl BlockStoreIterator {
async fn new(manager: &BlockManager) -> Result<Self, Error> {
let root_dir = manager.data_dir.clone();
let read_root_dir = fs::read_dir(&root_dir).await?;
Ok(Self {
path: vec![read_root_dir],
})
}
async fn next(&mut self) -> Result<Option<Hash>, Error> {
loop {
if let Some(reader) = self.path.last_mut() {
if let Some(data_dir_ent) = reader.next_entry().await? {
let name = data_dir_ent.file_name();
let name = if let Ok(n) = name.into_string() {
n
} else {
continue;
};
let ent_type = data_dir_ent.file_type().await?;
let name = name.strip_suffix(".zst").unwrap_or(&name);
if name.len() == 2 && hex::decode(&name).is_ok() && ent_type.is_dir() {
let read_child_dir = fs::read_dir(&data_dir_ent.path()).await?;
self.path.push(read_child_dir);
continue;
} else if name.len() == 64 {
let hash_bytes = if let Ok(h) = hex::decode(&name) {
h
} else {
continue;
};
let mut hash = [0u8; 32];
hash.copy_from_slice(&hash_bytes[..]);
return Ok(Some(hash.into()));
}
} else {
self.path.pop();
continue;
}
} else {
return Ok(None);
}
}
}
}
|
