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fix: universal compaction condition (#97)

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Signed-off-by: Alex Chi <iskyzh@gmail.com>
This commit is contained in:
Alex Chi Z.
2024-11-12 21:27:00 -05:00
committed by GitHub
parent b84dd3838f
commit 9cca6ad420
12 changed files with 107 additions and 29 deletions
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19
mini-lsm-mvcc/src/compact/tiered.rs
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@@ -16,6 +16,7 @@ pub struct TieredCompactionOptions {
pub max_size_amplification_percent: usize,
pub size_ratio: usize,
pub min_merge_width: usize,
pub max_merge_width: Option<usize>,
}
pub struct TieredCompactionController {
@@ -61,25 +62,29 @@ impl TieredCompactionController {
for id in 0..(snapshot.levels.len() - 1) {
size += snapshot.levels[id].1.len();
let next_level_size = snapshot.levels[id + 1].1.len();
let current_size_ratio = size as f64 / next_level_size as f64;
if current_size_ratio >= size_ratio_trigger && id + 2 >= self.options.min_merge_width {
let current_size_ratio = next_level_size as f64 / size as f64;
if current_size_ratio > size_ratio_trigger && id + 1 >= self.options.min_merge_width {
println!(
"compaction triggered by size ratio: {}",
current_size_ratio * 100.0
"compaction triggered by size ratio: {} > {}",
current_size_ratio * 100.0,
size_ratio_trigger * 100.0
);
return Some(TieredCompactionTask {
tiers: snapshot
.levels
.iter()
.take(id + 2)
.take(id + 1)
.cloned()
.collect::<Vec<_>>(),
bottom_tier_included: id + 2 >= snapshot.levels.len(),
bottom_tier_included: id + 1 >= snapshot.levels.len(),
});
}
}
// trying to reduce sorted runs without respecting size ratio
let num_tiers_to_take = snapshot.levels.len() - self.options.num_tiers + 2;
let num_tiers_to_take = snapshot
.levels
.len()
.min(self.options.max_merge_width.unwrap_or(usize::MAX));
println!("compaction triggered by reducing sorted runs");
return Some(TieredCompactionTask {
tiers: snapshot