runtime: swap im for imbl in StakesCache

Cargo.toml

@@ -275,7 +275,7 @@ histogram = "0.6.9"
 http = "1.4.0"
 humantime = "2.3.0"
 hyper-util = "0.1.20"
-im = "15.1.0"
+imbl = "7.0.0"
 indexmap = "2.13.1"
 indicatif = "0.18.4"
 io-uring = { version = "0.7.11", features = ["io_safety"] }

runtime/Cargo.toml

@@ -68,7 +68,7 @@ bincode = { workspace = true }
 bytemuck = { workspace = true }
 crossbeam-channel = { workspace = true }
 dashmap = { workspace = true, features = ["rayon", "raw-api", "serde"] }
-im = { workspace = true, features = ["rayon", "serde"] }
+imbl = { workspace = true, features = ["rayon", "serde"] }
 itertools = { workspace = true }
 libc = { workspace = true }
 log = { workspace = true }

runtime/src/bank/partitioned_epoch_rewards/distribution.rs

@@ -190,7 +190,7 @@ impl Bank {
     }
 
     fn build_updated_stake_reward(
-        stakes_cache_accounts: &im::HashMap<Pubkey, StakeAccount<Delegation>>,
+        stakes_cache_accounts: &imbl::HashMap<Pubkey, StakeAccount<Delegation>>,
         partitioned_stake_reward: &PartitionedStakeReward,
     ) -> Result<StakeReward, DistributionError> {
         let stake_account = stakes_cache_accounts

runtime/src/epoch_stakes.rs

@@ -205,7 +205,7 @@ impl VersionedEpochStakes {
             SerdeStakesToStakeFormat::Account(crate::stakes::Stakes::new_for_tests(
                 0,
                 solana_vote::vote_account::VoteAccounts::from(Arc::new(vote_accounts_hash_map)),
-                im::HashMap::default(),
+                imbl::HashMap::default(),
             )),
             leader_schedule_epoch,
         )
@@ -410,7 +410,7 @@ impl From<DeserializableEpochStakes> for EpochStakes {
 
 /// Snapshot epoch stakes contain delegations, but the main EpochStakes no longer uses them.
 /// This fn does custom deserialization to visit-and-ignore the delegations,
-/// avoiding the need to construct an expensive im::HashMap.
+/// avoiding the need to construct an expensive imbl::HashMap.
 fn deserialize_and_ignore_stake_delegations<'de, D>(deserializer: D) -> Result<(), D::Error>
 where
     D: Deserializer<'de>,
@@ -698,7 +698,7 @@ pub(crate) mod tests {
         let stakes = Stakes::new_for_tests(
             epoch,
             vote_accounts,
-            im::HashMap::from_iter([(stake_pubkey, stake_account)]),
+            imbl::HashMap::from_iter([(stake_pubkey, stake_account)]),
         );
 
         // ensure stake delegations start off *not* empty