Shrink HashMaps and Vectors

Shrink HashMaps and Vectors of downloaders and Verification queue to reduce the memory usage when syncing.

Author: HoOngEe

core/src/verification/queue/mod.rs

@@ -408,6 +408,7 @@ impl<K: Kind> VerificationQueue<K> {
  *td -= score;
  }
  }
+ processing.shrink_to_fit();
  processing.is_empty()
  }
 
@@ -429,6 +430,7 @@ impl<K: Kind> VerificationQueue<K> {
  *td -= score;
  }
  }
+ processing.shrink_to_fit();
 
  let mut new_verified = VecDeque::new();
  let mut removed_size = 0;
@@ -444,6 +446,7 @@ impl<K: Kind> VerificationQueue<K> {
  new_verified.push_back(output);
  }
  }
+ processing.shrink_to_fit();
 
  self.verification.sizes.verified.fetch_sub(removed_size, AtomicOrdering::SeqCst);
  *verified = new_verified;

sync/src/block/downloader/body.rs

@@ -69,6 +69,7 @@ impl BodyDownloader {
  self.downloaded.insert(hash, body);
  }
  }
+ self.downloading.shrink_to_fit();
  }
 
  pub fn add_target(&mut self, header: &Header, parent: &Header) {
@@ -93,13 +94,17 @@ impl BodyDownloader {
  self.downloading.remove(hash);
  self.downloaded.remove(hash);
  }
+ self.targets.shrink_to_fit();
+ self.downloading.shrink_to_fit();
+ self.downloaded.shrink_to_fit();
  }
 
  pub fn reset_downloading(&mut self, hashes: &[H256]) {
  cdebug!(SYNC, "Remove downloading by timeout {:?}", hashes);
  for hash in hashes {
  self.downloading.remove(&hash);
  }
+ self.downloading.shrink_to_fit();
  }
 
  pub fn drain(&mut self) -> Vec<(H256, Vec<UnverifiedTransaction>)> {
@@ -111,7 +116,9 @@ impl BodyDownloader {
  break
  }
  }
+ self.downloaded.shrink_to_fit();
  self.targets.drain(0..result.len());
+ self.targets.shrink_to_fit();
  result
  }
 }

sync/src/block/downloader/header.rs

@@ -187,6 +187,7 @@ impl HeaderDownloader {
  }
  }
  }
+ self.queued.shrink_to_fit();
  }
 
  pub fn mark_as_queued(&mut self, hashes: Vec<H256>) {
@@ -195,5 +196,6 @@ impl HeaderDownloader {
  self.queued.insert(hash, header);
  }
  }
+ self.downloaded.shrink_to_fit();
  }
 }