Increase the maximum of ancient slots allowed to be not combined

accounts-db/src/accounts_db.rs

@@ -146,6 +146,10 @@ const SHRINK_COLLECT_CHUNK_SIZE: usize = 50;
 /// candidates for shrinking.
 const SHRINK_INSERT_ANCIENT_THRESHOLD: usize = 10;
 
+/// Default value for the number of ancient storages the ancient slot
+/// combining should converge to.
+pub const MAX_ANCIENT_SLOTS_DEFAULT: usize = 100_000;
+
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
 pub enum CreateAncientStorage {
  /// ancient storages are created by appending
@@ -593,9 +597,17 @@ pub struct AccountsAddRootTiming {
  pub store_us: u64,
 }
 
-/// if negative, this many accounts older than # slots in epoch are still treated as modern (ie. non-ancient).
-/// Slots older than # slots in epoch - this # are then treated as ancient and subject to packing.
-const ANCIENT_APPEND_VEC_DEFAULT_OFFSET: Option<i64> = Some(-10_000);
+/// Slots older the "number of slots in an epoch minus this number"
+/// than max root are treated as ancient and subject to packing.
+/// | older |<- slots in an epoch ->| max root
+/// | older |<- offset ->| |
+/// | ancient | modern |
+///
+/// If this is negative, this many slots older than the number of
+/// slots in epoch are still treated as modern (ie. non-ancient).
+/// | older |<- abs(offset) ->|<- slots in an epoch ->| max root
+/// | ancient | modern |
+const ANCIENT_APPEND_VEC_DEFAULT_OFFSET: Option<i64> = Some(100_000);
 
 #[derive(Debug, Default, Clone)]
 pub struct AccountsDbConfig {
@@ -15146,10 +15158,9 @@ pub mod tests {
  let slots_per_epoch = config.epoch_schedule.slots_per_epoch;
  assert_ne!(slot, 0);
  let offset = 10;
- // no ancient append vecs, so always 0
  assert_eq!(
  db.get_oldest_non_ancient_slot_for_hash_calc_scan(slots_per_epoch + offset, &config),
- expected(0)
+ expected(db.ancient_append_vec_offset.unwrap() as u64 + offset + 1)
  );
  // ancient append vecs enabled (but at 0 offset), so can be non-zero
  db.ancient_append_vec_offset = Some(0);
@@ -15877,52 +15888,55 @@ pub mod tests {
  assert!(db
  .get_sorted_potential_ancient_slots(oldest_non_ancient_slot)
  .is_empty());
- let root0 = 0;
- db.add_root(root0);
- let root1 = 1;
+ let root1 = MAX_ANCIENT_SLOTS_DEFAULT as u64 + ancient_append_vec_offset as u64 + 1;
  db.add_root(root1);
+ let root2 = root1 + 1;
+ db.add_root(root2);
  let oldest_non_ancient_slot = db.get_oldest_non_ancient_slot(&epoch_schedule);
  assert!(db
  .get_sorted_potential_ancient_slots(oldest_non_ancient_slot)
  .is_empty());
  let completed_slot = epoch_schedule.slots_per_epoch;
- db.accounts_index.add_root(completed_slot);
+ db.accounts_index.add_root(AccountsDb::apply_offset_to_slot(
+ completed_slot,
+ ancient_append_vec_offset,
+ ));
  let oldest_non_ancient_slot = db.get_oldest_non_ancient_slot(&epoch_schedule);
  // get_sorted_potential_ancient_slots uses 'less than' as opposed to 'less or equal'
  // so, we need to get more than an epoch away to get the first valid root
  assert!(db
  .get_sorted_potential_ancient_slots(oldest_non_ancient_slot)
  .is_empty());
- let completed_slot = epoch_schedule.slots_per_epoch + root0;
+ let completed_slot = epoch_schedule.slots_per_epoch + root1;
  db.accounts_index.add_root(AccountsDb::apply_offset_to_slot(
  completed_slot,
- -ancient_append_vec_offset,
+ ancient_append_vec_offset,
  ));
  let oldest_non_ancient_slot = db.get_oldest_non_ancient_slot(&epoch_schedule);
  assert_eq!(
  db.get_sorted_potential_ancient_slots(oldest_non_ancient_slot),
- vec![root0]
+ vec![root1, root2]
  );
- let completed_slot = epoch_schedule.slots_per_epoch + root1;
+ let completed_slot = epoch_schedule.slots_per_epoch + root2;
  db.accounts_index.add_root(AccountsDb::apply_offset_to_slot(
  completed_slot,
- -ancient_append_vec_offset,
+ ancient_append_vec_offset,
  ));
  let oldest_non_ancient_slot = db.get_oldest_non_ancient_slot(&epoch_schedule);
  assert_eq!(
  db.get_sorted_potential_ancient_slots(oldest_non_ancient_slot),
- vec![root0, root1]
+ vec![root1, root2]
  );
  db.accounts_index
  .roots_tracker
  .write()
  .unwrap()
  .alive_roots
- .remove(&root0);
+ .remove(&root1);
  let oldest_non_ancient_slot = db.get_oldest_non_ancient_slot(&epoch_schedule);
  assert_eq!(
  db.get_sorted_potential_ancient_slots(oldest_non_ancient_slot),
- vec![root1]
+ vec![root2]
  );
  });
 

accounts-db/src/ancient_append_vecs.rs

@@ -11,6 +11,7 @@ use {
  stats::{ShrinkAncientStats, ShrinkStatsSub},
  AccountFromStorage, AccountStorageEntry, AccountsDb, AliveAccounts,
  GetUniqueAccountsResult, ShrinkCollect, ShrinkCollectAliveSeparatedByRefs,
+ MAX_ANCIENT_SLOTS_DEFAULT,
  },
  accounts_file::AccountsFile,
  active_stats::ActiveStatItem,
@@ -342,8 +343,9 @@ impl AccountsDb {
  can_randomly_shrink: bool,
  ) {
  let tuning = PackedAncientStorageTuning {
- // only allow 10k slots old enough to be ancient
- max_ancient_slots: 10_000,
+ // Slots old enough to be ancient. Setting this parameter
+ // to 100k makes ancient storages to be approx 5M.
+ max_ancient_slots: MAX_ANCIENT_SLOTS_DEFAULT,
  // Don't re-pack anything just to shrink.
  // shrink_candidate_slots will handle these old storages.
  percent_of_alive_shrunk_data: 0,