[thin_restore (rust)] rewrite the btree_builder
Now copes with adding shared leaves.
This commit is contained in:
Joe Thornber
parent
443b3c8f0b
commit
04e0eb3a66
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@ -13,6 +13,56 @@ use crate::write_batcher::*;
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//------------------------------------------
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/// A little ref counter abstraction. Used to manage counts for btree
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/// values (eg, the block/time in a thin mapping tree).
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pub trait RefCounter<Value> {
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fn get(&self, v: &Value) -> Result<u32>;
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fn inc(&mut self, v: &Value) -> Result<()>;
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fn dec(&mut self, v: &Value) -> Result<()>;
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}
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/// Wraps a space map up to become a RefCounter.
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struct SMRefCounter {
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sm: Arc<Mutex<dyn SpaceMap>>,
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}
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impl RefCounter<u64> for SMRefCounter {
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fn get(&self, v: &u64) -> Result<u32> {
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self.sm.lock().unwrap().get(*v)
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}
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fn inc(&mut self, v: &u64) -> Result<()> {
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self.sm.lock().unwrap().inc(*v, 1)
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}
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fn dec(&mut self, v: &u64) -> Result<()> {
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self.sm.lock().unwrap().dec(*v)?;
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Ok(())
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}
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}
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//------------------------------------------
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// Building a btree for a given set of values is straight forward.
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// But often we want to merge shared subtrees into the btree we're
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// building, which _is_ complicated. Requiring rebalancing of nodes,
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// and careful copy-on-write operations so we don't disturb the shared
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// subtree.
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//
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// To avoid these problems this code never produces shared internal nodes.
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// With the large fan out of btrees this isn't really a problem; we'll
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// allocate more nodes than optimum, but not many compared to the number
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// of leaves. Also we can pack the leaves much better than the kernel
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// does due to out of order insertions.
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//
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// There are thus two stages to building a btree.
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//
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// i) Produce a list of populated leaves. These leaves may well be shared.
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// ii) Build the upper levels of the btree above the leaves.
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//------------------------------------------
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/// Pack the given node ready to write to disk.
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fn pack_node<W: WriteBytesExt, V: Pack + Unpack>(node: &Node<V>, w: &mut W) -> Result<()> {
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match node {
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Node::Internal {
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@ -58,100 +108,13 @@ fn pack_node<W: WriteBytesExt, V: Pack + Unpack>(node: &Node<V>, w: &mut W) -> R
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Ok(())
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}
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//------------------------------------------
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fn calc_max_entries<V: Unpack>() -> usize {
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let elt_size = 8 + V::disk_size() as usize;
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((BLOCK_SIZE - NodeHeader::disk_size() as usize) / elt_size) as usize
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pub struct WriteResult {
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first_key: u64,
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loc: u64,
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}
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//------------------------------------------
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struct Entries<V> {
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pub max_entries: usize,
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entries: VecDeque<(u64, V)>,
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}
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enum Action<V> {
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EmitNode(Vec<u64>, Vec<V>), // keys, values
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}
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use Action::*;
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impl<V> Entries<V> {
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pub fn new(max_entries: usize) -> Entries<V> {
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Entries {
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max_entries,
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entries: VecDeque::new(),
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}
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}
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pub fn add_entry(&mut self, k: u64, v: V) -> Vec<Action<V>> {
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let mut result = Vec::new();
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if self.full() {
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let (keys, values) = self.pop(self.max_entries);
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result.push(EmitNode(keys, values));
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}
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self.entries.push_back((k, v));
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result
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}
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fn complete_(&mut self, result: &mut Vec<Action<V>>) {
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let n = self.entries.len();
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if n >= self.max_entries {
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let n1 = n / 2;
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let n2 = n - n1;
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let (keys1, values1) = self.pop(n1);
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let (keys2, values2) = self.pop(n2);
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result.push(EmitNode(keys1, values1));
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result.push(EmitNode(keys2, values2));
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} else if n > 0 {
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let (keys, values) = self.pop(n);
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result.push(EmitNode(keys, values));
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}
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}
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pub fn complete(&mut self) -> Vec<Action<V>> {
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let mut result = Vec::new();
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self.complete_(&mut result);
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result
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}
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fn full(&self) -> bool {
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self.entries.len() >= 2 * self.max_entries
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}
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fn pop(&mut self, count: usize) -> (Vec<u64>, Vec<V>) {
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let mut keys = Vec::new();
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let mut values = Vec::new();
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for _i in 0..count {
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let (k, v) = self.entries.pop_front().unwrap();
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keys.push(k);
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values.push(v);
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}
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(keys, values)
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}
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}
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//------------------------------------------
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#[allow(dead_code)]
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pub struct NodeSummary {
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block: u64,
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nr_entries: usize,
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key_low: u64,
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key_high: u64, // inclusive
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}
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//------------------------------------------
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fn write_node_<V: Unpack + Pack>(w: &mut WriteBatcher, mut node: Node<V>) -> Result<(u64, u64)> {
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/// Write a node to a free metadata block.
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fn write_node_<V: Unpack + Pack>(w: &mut WriteBatcher, mut node: Node<V>) -> Result<WriteResult> {
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let keys = node.get_keys();
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let first_key = keys.first().unwrap_or(&0u64).clone();
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@ -163,155 +126,380 @@ fn write_node_<V: Unpack + Pack>(w: &mut WriteBatcher, mut node: Node<V>) -> Res
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pack_node(&node, &mut cursor)?;
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w.write(b, checksum::BT::NODE)?;
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Ok((first_key, loc))
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Ok(WriteResult { first_key, loc })
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}
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fn write_leaf<V: Unpack + Pack>(
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w: &mut WriteBatcher,
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keys: Vec<u64>,
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values: Vec<V>,
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) -> Result<(u64, u64)> {
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let header = NodeHeader {
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block: 0,
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is_leaf: true,
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nr_entries: keys.len() as u32,
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max_entries: calc_max_entries::<V>() as u32,
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value_size: V::disk_size(),
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};
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let node = Node::Leaf {
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header,
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keys,
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values,
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};
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write_node_(w, node)
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/// A node writer takes a Vec of values and packs them into
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/// a btree node. It's up to the specific implementation to
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/// decide if it produces internal or leaf nodes.
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pub trait NodeIO<V: Unpack + Pack> {
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fn write(&self, w: &mut WriteBatcher, keys: Vec<u64>, values: Vec<V>) -> Result<WriteResult>;
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fn read(
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&self,
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engine: &Arc<dyn IoEngine + Send + Sync>,
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block: u64,
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) -> Result<(Vec<u64>, Vec<V>)>;
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}
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fn write_internal(w: &mut WriteBatcher, keys: Vec<u64>, values: Vec<u64>) -> Result<(u64, u64)> {
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let header = NodeHeader {
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block: 0,
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is_leaf: false,
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nr_entries: keys.len() as u32,
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max_entries: calc_max_entries::<u64>() as u32,
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value_size: u64::disk_size(),
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};
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struct LeafIO {}
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let node: Node<u64> = Node::Internal {
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header,
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keys,
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values,
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};
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impl<V: Unpack + Pack> NodeIO<V> for LeafIO {
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fn write(&self, w: &mut WriteBatcher, keys: Vec<u64>, values: Vec<V>) -> Result<WriteResult> {
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let header = NodeHeader {
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block: 0,
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is_leaf: true,
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nr_entries: keys.len() as u32,
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max_entries: calc_max_entries::<V>() as u32,
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value_size: V::disk_size(),
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};
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write_node_(w, node)
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let node = Node::Leaf {
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header,
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keys,
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values,
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};
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write_node_(w, node)
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}
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fn read(
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&self,
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engine: &Arc<dyn IoEngine + Send + Sync>,
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block: u64,
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) -> Result<(Vec<u64>, Vec<V>)> {
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let b = engine.read(block)?;
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let path = Vec::new();
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match unpack_node::<V>(&path, b.get_data(), true, true)? {
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Node::Internal { .. } => {
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panic!("unexpected internal node");
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}
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Node::Leaf { keys, values, .. } => Ok((keys, values)),
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}
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}
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}
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pub struct Builder<V: Unpack + Pack> {
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w: WriteBatcher,
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entries: Entries<V>,
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struct InternalIO {}
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max_internal_entries: usize,
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internal_entries: Vec<Entries<u64>>,
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impl NodeIO<u64> for InternalIO {
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fn write(&self, w: &mut WriteBatcher, keys: Vec<u64>, values: Vec<u64>) -> Result<WriteResult> {
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let header = NodeHeader {
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block: 0,
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is_leaf: false,
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nr_entries: keys.len() as u32,
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max_entries: calc_max_entries::<u64>() as u32,
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value_size: u64::disk_size(),
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};
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root: u64,
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let node: Node<u64> = Node::Internal {
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header,
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keys,
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values,
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};
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write_node_(w, node)
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}
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fn read(
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&self,
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engine: &Arc<dyn IoEngine + Send + Sync>,
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block: u64,
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) -> Result<(Vec<u64>, Vec<u64>)> {
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let b = engine.read(block)?;
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let path = Vec::new();
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match unpack_node::<u64>(&path, b.get_data(), true, true)? {
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Node::Internal { keys, values, .. } => Ok((keys, values)),
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Node::Leaf { .. } => {
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panic!("unexpected leaf node");
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}
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}
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}
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}
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impl<V: Unpack + Pack> Builder<V> {
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//------------------------------------------
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/// What is the maximum number of entries of a given size we can fit in
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/// a btree node?
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fn calc_max_entries<V: Unpack>() -> usize {
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let elt_size = 8 + V::disk_size() as usize;
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((BLOCK_SIZE - NodeHeader::disk_size() as usize) / elt_size) as usize
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}
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//------------------------------------------
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/// This takes a sequence of values or nodes, and builds a vector of leaf nodes.
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/// Care is taken to make sure that all nodes are at least half full unless there's
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/// only a single node.
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pub struct NodeBuilder<V: Pack + Unpack> {
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batcher: WriteBatcher,
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nio: Box<dyn NodeIO<V>>,
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value_rc: Box<dyn RefCounter<V>>,
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max_entries_per_node: usize,
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values: VecDeque<(u64, V)>,
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nodes: Vec<NodeSummary>,
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}
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/// When the builder is including pre-built nodes it has to decide whether
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/// to use the node as given, or read it and import the values directly
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/// for balancing reasons. This struct is used to stop us re-reading
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/// the NodeHeaders of nodes that are shared multiple times.
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#[derive(Clone)]
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pub struct NodeSummary {
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block: u64,
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key: u64,
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nr_entries: usize,
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/// This node was passed in pre-built. Important for deciding if
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/// we need to adjust the ref counts if we unpack.
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shared: bool,
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}
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impl<V: Pack + Unpack + Clone> NodeBuilder<V> {
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/// Create a new NodeBuilder
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pub fn new(
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engine: Arc<dyn IoEngine + Send + Sync>,
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sm: Arc<Mutex<dyn SpaceMap>>,
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) -> Builder<V> {
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let max_entries = calc_max_entries::<V>();
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let max_internal_entries = calc_max_entries::<u64>();
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Builder {
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w: WriteBatcher::new(engine, sm, 256),
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entries: Entries::new(max_entries),
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max_internal_entries,
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internal_entries: Vec::new(),
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root: 0,
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batcher: WriteBatcher,
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nio: Box<dyn NodeIO<V>>,
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value_rc: Box<dyn RefCounter<V>>,
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) -> Self {
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NodeBuilder {
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batcher,
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nio,
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value_rc,
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max_entries_per_node: calc_max_entries::<V>(),
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values: VecDeque::new(),
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nodes: Vec::new(),
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}
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}
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pub fn add_entry(&mut self, k: u64, v: V) -> Result<()> {
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let actions = self.entries.add_entry(k, v);
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for a in actions {
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self.perform_action(a)?;
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/// Push a single value. This may emit a new node, hence the Result
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/// return type. The value's ref count will be incremented.
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pub fn push_value(&mut self, key: u64, val: V) -> Result<()> {
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// Have we got enough values to emit a node? We try and keep
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// at least max_entries_per_node entries unflushed so we
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// can ensure the final node is balanced properly.
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if self.values.len() == self.max_entries_per_node * 2 {
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self.emit_node()?;
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}
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self.value_rc.inc(&val)?;
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self.values.push_back((key, val));
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Ok(())
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}
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pub fn add_leaf_node(&mut self, leaf: &NodeSummary) -> Result<()> {
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match leaf.nr_entries {
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n if n == 0 => {
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// Do nothing
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},
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n if n < (self.entries.max_entries / 2) => {
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// FIXME: what if we've already queued a handful of entries for a node?
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// Add the entries individually
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todo!();
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},
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_n => {
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let actions = self.entries.complete();
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for a in actions {
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self.perform_action(a)?;
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}
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self.add_internal_entry(0, leaf.key_low, leaf.block)?;
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/// Push a number of prebuilt, shared nodes. The builder may decide to not
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/// use a shared node, instead reading the values and packing them
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/// directly. This may do IO to emit nodes, so returns a Result.
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/// Any shared nodes that are used have their block incremented in
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/// the space map. Will only increment the ref count for values
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/// contained in the nodes if it unpacks them.
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pub fn push_nodes(&mut self, nodes: &Vec<NodeSummary>) -> Result<()> {
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assert!(nodes.len() > 0);
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// As a sanity check we make sure that all the shared nodes contain the
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// minimum nr of entries.
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let half_full = self.max_entries_per_node / 2;
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for n in nodes {
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if n.nr_entries < half_full {
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panic!("under populated node");
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}
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}
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// Decide if we're going to use the pre-built nodes.
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if self.values.len() < half_full {
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// To avoid writing an under populated node we have to grab some
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// values from the first of the shared nodes.
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let (keys, values) = self.read_node(nodes.get(0).unwrap().block)?;
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for i in 0..keys.len() {
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self.value_rc.inc(&values[i])?;
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self.values.push_back((keys[i], values[i].clone()));
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}
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// Flush all the values.
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self.emit_all()?;
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// Add the remaining nodes.
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for i in 1..nodes.len() {
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let n = nodes.get(i).unwrap();
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self.batcher.sm.lock().unwrap().inc(n.block, 1)?;
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self.nodes.push(n.clone());
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}
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} else {
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// Flush all the values.
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self.emit_all()?;
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// add the nodes
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for n in nodes {
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self.batcher.sm.lock().unwrap().inc(n.block, 1)?;
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self.nodes.push(n.clone());
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}
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}
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Ok(())
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}
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pub fn complete(mut self) -> Result<u64> {
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let actions = self.entries.complete();
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for a in actions {
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self.perform_action(a)?;
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/// Signal that no more values or nodes will be pushed. Returns a
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/// vector of the built nodes. Consumes the builder.
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pub fn complete(mut self) -> Result<Vec<NodeSummary>> {
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let half_full = self.max_entries_per_node / 2;
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if (self.nodes.len() > 0) && (self.values.len() < half_full) {
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// We don't have enough values to emit a node. So we're going to
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// have to rebalance with the previous node.
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self.unshift_node()?;
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}
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self.w.flush()?;
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Ok(self.root)
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self.emit_all()?;
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Ok(self.nodes)
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}
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//--------------------
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//-------------------------
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fn add_internal_entry(&mut self, level: usize, k: u64, v: u64) -> Result<()> {
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if self.internal_entries.len() == level {
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self.internal_entries
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.push(Entries::new(self.max_internal_entries));
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// We're only interested in the keys and values from the node, and
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// not whether it's a leaf or internal node.
|
||||
fn read_node(&self, block: u64) -> Result<(Vec<u64>, Vec<V>)> {
|
||||
self.nio.read(&self.batcher.engine, block)
|
||||
}
|
||||
|
||||
/// Writes a node with the first 'nr_entries' values.
|
||||
fn emit_values(&mut self, nr_entries: usize) -> Result<()> {
|
||||
assert!(self.values.len() <= nr_entries);
|
||||
|
||||
// Write the node
|
||||
let mut keys = Vec::new();
|
||||
let mut values = Vec::new();
|
||||
|
||||
for _i in 0..nr_entries {
|
||||
let (k, v) = self.values.pop_front().unwrap();
|
||||
keys.push(k);
|
||||
values.push(v);
|
||||
}
|
||||
|
||||
let actions = self.internal_entries[level].add_entry(k, v);
|
||||
|
||||
for a in actions {
|
||||
self.perform_internal_action(level, a)?;
|
||||
}
|
||||
let wresult = self.nio.write(&mut self.batcher, keys, values)?;
|
||||
|
||||
// Push a summary to the 'nodes' vector.
|
||||
self.nodes.push(NodeSummary {
|
||||
block: wresult.loc,
|
||||
key: wresult.first_key,
|
||||
nr_entries,
|
||||
shared: false,
|
||||
});
|
||||
Ok(())
|
||||
}
|
||||
|
||||
fn perform_internal_action(&mut self, level: usize, action: Action<u64>) -> Result<()> {
|
||||
match action {
|
||||
EmitNode(keys, values) => {
|
||||
let (k, loc) = write_internal(&mut self.w, keys, values)?;
|
||||
self.add_internal_entry(level + 1, k, loc)?;
|
||||
self.root = loc;
|
||||
},
|
||||
}
|
||||
|
||||
Ok(())
|
||||
/// Writes a full node.
|
||||
fn emit_node(&mut self) -> Result<()> {
|
||||
self.emit_values(self.max_entries_per_node)
|
||||
}
|
||||
|
||||
fn perform_action<V2: Unpack + Pack>(&mut self, action: Action<V2>) -> Result<()> {
|
||||
match action {
|
||||
EmitNode(keys, values) => {
|
||||
let (k, loc) = write_leaf(&mut self.w, keys, values)?;
|
||||
self.add_internal_entry(0, k, loc)?;
|
||||
},
|
||||
/// Emits all remaining values. Panics if there are more than 2 *
|
||||
/// max_entries_per_node values.
|
||||
fn emit_all(&mut self) -> Result<()> {
|
||||
match self.values.len() {
|
||||
0 => {
|
||||
// There's nothing to emit
|
||||
Ok(())
|
||||
}
|
||||
n if n <= self.max_entries_per_node => {
|
||||
// Emit a single node.
|
||||
self.emit_values(n)
|
||||
}
|
||||
n if n <= self.max_entries_per_node * 2 => {
|
||||
// Emit two nodes.
|
||||
let n1 = n / 2;
|
||||
let n2 = n - n1;
|
||||
self.emit_values(n1)?;
|
||||
self.emit_values(n2)
|
||||
}
|
||||
_ => {
|
||||
panic!("self.values shouldn't have more than 2 * max_entries_per_node entries");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Pops the last node, and prepends it's values to 'self.values'. Used
|
||||
/// to rebalance when we have insufficient values for a final node. The
|
||||
/// node is decremented in the space map.
|
||||
fn unshift_node(&mut self) -> Result<()> {
|
||||
let ls = self.nodes.pop().unwrap();
|
||||
let (keys, values) = self.read_node(ls.block)?;
|
||||
self.batcher.sm.lock().unwrap().dec(ls.block)?;
|
||||
|
||||
let mut vals = VecDeque::new();
|
||||
|
||||
for i in 0..keys.len() {
|
||||
// We only need to inc the values if the node was pre built.
|
||||
if ls.shared {
|
||||
self.value_rc.inc(&values[i])?;
|
||||
}
|
||||
vals.push_back((keys[i], values[i].clone()));
|
||||
}
|
||||
|
||||
vals.append(&mut self.values);
|
||||
std::mem::swap(&mut self.values, &mut vals);
|
||||
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
|
||||
//------------------------------------------
|
||||
|
||||
pub struct Builder<V: Unpack + Pack> {
|
||||
engine: Arc<dyn IoEngine + Send + Sync>,
|
||||
sm: Arc<Mutex<dyn SpaceMap>>,
|
||||
leaf_builder: NodeBuilder<V>,
|
||||
}
|
||||
|
||||
const BATCH_SIZE: usize = 128;
|
||||
|
||||
impl<V: Unpack + Pack + Clone> Builder<V> {
|
||||
pub fn new(
|
||||
engine: Arc<dyn IoEngine + Send + Sync>,
|
||||
sm: Arc<Mutex<dyn SpaceMap>>,
|
||||
value_rc: Box<dyn RefCounter<V>>,
|
||||
) -> Builder<V> {
|
||||
Builder {
|
||||
engine: engine.clone(),
|
||||
sm: sm.clone(),
|
||||
leaf_builder: NodeBuilder::new(
|
||||
WriteBatcher::new(engine.clone(), sm.clone(), BATCH_SIZE),
|
||||
Box::new(LeafIO {}),
|
||||
value_rc,
|
||||
),
|
||||
}
|
||||
}
|
||||
|
||||
pub fn push_value(&mut self, k: u64, v: V) -> Result<()> {
|
||||
self.leaf_builder.push_value(k, v)
|
||||
}
|
||||
|
||||
pub fn push_leaves(&mut self, leaves: &Vec<NodeSummary>) -> Result<()> {
|
||||
self.leaf_builder.push_nodes(leaves)
|
||||
}
|
||||
|
||||
pub fn complete(self) -> Result<u64> {
|
||||
let mut nodes = self.leaf_builder.complete()?;
|
||||
|
||||
// Now we iterate, adding layers of internal nodes until we end
|
||||
// up with a single root.
|
||||
while nodes.len() > 1 {
|
||||
let mut builder = NodeBuilder::new(
|
||||
WriteBatcher::new(self.engine.clone(), self.sm.clone(), BATCH_SIZE),
|
||||
Box::new(InternalIO {}),
|
||||
Box::new(SMRefCounter {
|
||||
sm: self.sm.clone(),
|
||||
}),
|
||||
);
|
||||
|
||||
for n in nodes {
|
||||
builder.push_value(n.key, n.block)?;
|
||||
}
|
||||
|
||||
nodes = builder.complete()?;
|
||||
}
|
||||
|
||||
assert!(nodes.len() == 1);
|
||||
Ok(nodes[0].block)
|
||||
}
|
||||
}
|
||||
|
||||
//------------------------------------------
|
||||
|
|
|
|||
|
|
@ -2,8 +2,8 @@ use anyhow::{anyhow, Result};
|
|||
use byteorder::{LittleEndian, WriteBytesExt};
|
||||
use fixedbitset::FixedBitSet;
|
||||
use nom::{multi::count, number::complete::*, IResult};
|
||||
use std::sync::{Arc, Mutex};
|
||||
use std::boxed::Box;
|
||||
use std::sync::{Arc, Mutex};
|
||||
|
||||
use crate::io_engine::*;
|
||||
use crate::pdata::unpack::{Pack, Unpack};
|
||||
|
|
@ -226,13 +226,22 @@ pub trait SpaceMap {
|
|||
fn get_nr_allocated(&self) -> Result<u64>;
|
||||
fn get(&self, b: u64) -> Result<u32>;
|
||||
|
||||
// Returns the old ref count
|
||||
/// Returns the old ref count
|
||||
fn set(&mut self, b: u64, v: u32) -> Result<u32>;
|
||||
|
||||
fn inc(&mut self, begin: u64, len: u64) -> Result<()>;
|
||||
|
||||
// Finds a block with a zero reference count. Increments the
|
||||
// count.
|
||||
/// Returns true if the block is now free
|
||||
fn dec(&mut self, b: u64) -> Result<bool> {
|
||||
let old = self.get(b)?;
|
||||
assert!(old > 0);
|
||||
self.set(b, old - 1)?;
|
||||
|
||||
Ok(old == 1)
|
||||
}
|
||||
|
||||
/// Finds a block with a zero reference count. Increments the
|
||||
/// count.
|
||||
fn alloc(&mut self) -> Result<Option<u64>>;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -1,9 +1,62 @@
|
|||
use anyhow::Result;
|
||||
|
||||
use std::collections::{BTreeMap, BTreeSet};
|
||||
use std::fs::OpenOptions;
|
||||
use std::path::Path;
|
||||
use std::sync::Arc;
|
||||
|
||||
use crate::report::*;
|
||||
|
||||
use crate::thin::block_time::*;
|
||||
use crate::thin::device_detail::*;
|
||||
use crate::thin::superblock::*;
|
||||
use crate::thin::xml::{self, *};
|
||||
|
||||
//------------------------------------------
|
||||
|
||||
#[derive(Default)]
|
||||
struct Pass1 {
|
||||
//
|
||||
}
|
||||
|
||||
impl MetadataVisitor for Pass1 {
|
||||
fn superblock_b(&mut self, sb: &xml::Superblock) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn superblock_e(&mut self) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn def_shared_b(&mut self, name: &str) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn def_shared_e(&mut self) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn device_b(&mut self, d: &Device) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn device_e(&mut self) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn map(&mut self, m: &Map) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn ref_shared(&mut self, name: &str) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
|
||||
fn eof(&mut self) -> Result<Visit> {
|
||||
todo!();
|
||||
}
|
||||
}
|
||||
|
||||
//------------------------------------------
|
||||
|
||||
pub struct ThinRestoreOptions<'a> {
|
||||
|
|
@ -15,8 +68,16 @@ pub struct ThinRestoreOptions<'a> {
|
|||
|
||||
//------------------------------------------
|
||||
|
||||
pub fn restore(_opts: ThinRestoreOptions) -> Result<()> {
|
||||
todo!();
|
||||
pub fn restore(opts: ThinRestoreOptions) -> Result<()> {
|
||||
let input = OpenOptions::new()
|
||||
.read(true)
|
||||
.write(false)
|
||||
.open(opts.input)?;
|
||||
|
||||
let mut pass = Pass1::default();
|
||||
xml::read(input, &mut pass)?;
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
//------------------------------------------
|
||||
|
|
|
|||
|
|
@ -7,9 +7,10 @@ use crate::pdata::space_map::*;
|
|||
|
||||
//------------------------------------------
|
||||
|
||||
#[derive(Clone)]
|
||||
pub struct WriteBatcher {
|
||||
engine: Arc<dyn IoEngine + Send + Sync>,
|
||||
sm: Arc<Mutex<dyn SpaceMap>>,
|
||||
pub engine: Arc<dyn IoEngine + Send + Sync>,
|
||||
pub sm: Arc<Mutex<dyn SpaceMap>>,
|
||||
|
||||
batch_size: usize,
|
||||
queue: Vec<Block>,
|
||||
|
|
|
|||
Loading…
Reference in New Issue