(Bank/Snapshot) Add prior_roots to bank fields.

core/tests/snapshots.rs

@@ -98,6 +98,10 @@ mod tests {
         tempfile::TempDir,
     };
 
+    DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_3_0, Development, V1_3_0_Development);
+    DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_3_0, Devnet, V1_3_0_Devnet);
+    DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_3_0, Testnet, V1_3_0_Testnet);
+    DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_3_0, MainnetBeta, V1_3_0_MainnetBeta);
     DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_2_0, Development, V1_2_0_Development);
     DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_2_0, Devnet, V1_2_0_Devnet);
     DEFINE_SNAPSHOT_VERSION_PARAMETERIZED_TEST_FUNCTIONS!(V1_2_0, Testnet, V1_2_0_Testnet);

runtime/src/bank.rs

@@ -919,12 +919,13 @@ pub(crate) struct BankFieldsToDeserialize {
     pub(crate) stakes: Stakes,
     pub(crate) epoch_stakes: HashMap<Epoch, EpochStakes>,
     pub(crate) is_delta: bool,
+    pub(crate) prior_roots: Vec<Slot>,
 }
 
-// Bank's common fields shared by all supported snapshot versions for serialization.
-// This is separated from BankFieldsToDeserialize to avoid cloning by using refs.
-// So, sync fields with BankFieldsToDeserialize!
-// all members are made public to keep Bank private and to make versioned serializer workable on this
+/// Bank's common fields shared by all supported snapshot versions for serialization.
+/// This is separated from BankFieldsToDeserialize to avoid cloning by using refs.
+/// So, sync fields with BankFieldsToDeserialize!
+/// all members are made public to keep Bank private and to make versioned serializer workable on this
 #[derive(Debug)]
 pub(crate) struct BankFieldsToSerialize<'a> {
     pub(crate) blockhash_queue: &'a RwLock<BlockhashQueue>,
@@ -957,6 +958,7 @@ pub(crate) struct BankFieldsToSerialize<'a> {
     pub(crate) stakes: &'a StakesCache,
     pub(crate) epoch_stakes: &'a HashMap<Epoch, EpochStakes>,
     pub(crate) is_delta: bool,
+    pub(crate) prior_roots: Vec<Slot>,
 }
 
 // Can't derive PartialEq because RwLock doesn't implement PartialEq
@@ -995,6 +997,7 @@ impl PartialEq for Bank {
             && *self.stakes_cache.stakes() == *other.stakes_cache.stakes()
             && self.epoch_stakes == other.epoch_stakes
             && self.is_delta.load(Relaxed) == other.is_delta.load(Relaxed)
+            && self.prior_roots == other.prior_roots
     }
 }
 
@@ -1179,6 +1182,14 @@ pub struct Bank {
     /// stream for the slot == self.slot
     is_delta: AtomicBool,
 
+    /// The list of roots which are no longer roots in the current bank instance.
+    /// As we eliminate rewrites/ancient append vec, we need to the ability to
+    /// remember slots within that last epoch that WERE roots even if they no
+    /// longer contain any accounts.  Without remembering those prior roots,
+    /// accounts that we skip rewrites might have their rent collection time
+    /// point to the incorrect roots as their correct roots were removed.
+    pub prior_roots: Vec<Slot>,
+
     /// The builtin programs
     builtin_programs: BuiltinPrograms,
 
@@ -1352,6 +1363,7 @@ impl Bank {
             stakes_cache: StakesCache::default(),
             epoch_stakes: HashMap::<Epoch, EpochStakes>::default(),
             is_delta: AtomicBool::default(),
+            prior_roots: Vec::<Slot>::default(),
             builtin_programs: BuiltinPrograms::default(),
             compute_budget: Option::<ComputeBudget>::default(),
             builtin_feature_transitions: Arc::<Vec<BuiltinFeatureTransition>>::default(),
@@ -1668,6 +1680,7 @@ impl Bank {
             ancestors: Ancestors::default(),
             hash: RwLock::new(Hash::default()),
             is_delta: AtomicBool::new(false),
+            prior_roots: parent.prior_roots.clone(),
             tick_height: AtomicU64::new(parent.tick_height.load(Relaxed)),
             signature_count: AtomicU64::new(0),
             builtin_programs,
@@ -1964,6 +1977,7 @@ impl Bank {
             stakes_cache: StakesCache::new(fields.stakes),
             epoch_stakes: fields.epoch_stakes,
             is_delta: AtomicBool::new(fields.is_delta),
+            prior_roots: fields.prior_roots,
             builtin_programs: new(),
             compute_budget: None,
             builtin_feature_transitions: new(),
@@ -2066,6 +2080,7 @@ impl Bank {
             stakes: &self.stakes_cache,
             epoch_stakes: &self.epoch_stakes,
             is_delta: self.is_delta.load(Relaxed),
+            prior_roots: self.prior_roots.clone(),
         }
     }
 

runtime/src/serde_snapshot.rs

@@ -46,6 +46,7 @@ use {
 };
 
 mod newer;
+mod older;
 mod storage;
 mod tests;
 mod utils;
@@ -57,6 +58,7 @@ pub(crate) use tests::reconstruct_accounts_db_via_serialization;
 #[derive(Copy, Clone, Eq, PartialEq)]
 pub(crate) enum SerdeStyle {
     Newer,
+    Older,
 }
 
 const MAX_STREAM_SIZE: u64 = 32 * 1024 * 1024 * 1024;
@@ -237,6 +239,7 @@ where
     }
     match serde_style {
         SerdeStyle::Newer => INTO!(newer),
+        SerdeStyle::Older => INTO!(older),
     }
     .map_err(|err| {
         warn!("bankrc_from_stream error: {:?}", err);
@@ -267,6 +270,7 @@ where
     }
     match serde_style {
         SerdeStyle::Newer => INTO!(newer),
+        SerdeStyle::Older => INTO!(older),
     }
     .map_err(|err| {
         warn!("bankrc_to_stream error: {:?}", err);

runtime/src/serde_snapshot/newer.rs

@@ -6,18 +6,12 @@ use {
     },
     crate::{ancestors::AncestorsForSerialization, stakes::StakesCache},
     solana_measure::measure::Measure,
-    std::{cell::RefCell, collections::HashSet, sync::RwLock},
+    solana_sdk::deserialize_utils::default_on_eof,
+    std::{cell::RefCell, sync::RwLock},
 };
 
 type AccountsDbFields = super::AccountsDbFields<SerializableAccountStorageEntry>;
 
-#[derive(Default, Clone, PartialEq, Debug, Deserialize, Serialize, AbiExample)]
-struct UnusedAccounts {
-    unused1: HashSet<Pubkey>,
-    unused2: HashSet<Pubkey>,
-    unused3: HashMap<Pubkey, u64>,
-}
-
 // Deserializable version of Bank which need not be serializable,
 // because it's handled by SerializableVersionedBank.
 // So, sync fields with it!
@@ -39,8 +33,6 @@ struct DeserializableVersionedBank {
     ns_per_slot: u128,
     genesis_creation_time: UnixTimestamp,
     slots_per_year: f64,
-    #[allow(dead_code)]
-    unused: u64,
     slot: Slot,
     epoch: Epoch,
     block_height: u64,
@@ -53,10 +45,10 @@ struct DeserializableVersionedBank {
     epoch_schedule: EpochSchedule,
     inflation: Inflation,
     stakes: Stakes,
-    #[allow(dead_code)]
-    unused_accounts: UnusedAccounts,
     epoch_stakes: HashMap<Epoch, EpochStakes>,
     is_delta: bool,
+    #[serde(deserialize_with = "default_on_eof")]
+    prior_roots: Vec<Slot>,
 }
 
 impl From<DeserializableVersionedBank> for BankFieldsToDeserialize {
@@ -92,6 +84,7 @@ impl From<DeserializableVersionedBank> for BankFieldsToDeserialize {
             stakes: dvb.stakes,
             epoch_stakes: dvb.epoch_stakes,
             is_delta: dvb.is_delta,
+            prior_roots: dvb.prior_roots,
         }
     }
 }
@@ -116,7 +109,6 @@ struct SerializableVersionedBank<'a> {
     ns_per_slot: u128,
     genesis_creation_time: UnixTimestamp,
     slots_per_year: f64,
-    unused: u64,
     slot: Slot,
     epoch: Epoch,
     block_height: u64,
@@ -129,9 +121,9 @@ struct SerializableVersionedBank<'a> {
     epoch_schedule: EpochSchedule,
     inflation: Inflation,
     stakes: &'a StakesCache,
-    unused_accounts: UnusedAccounts,
     epoch_stakes: &'a HashMap<Epoch, EpochStakes>,
     is_delta: bool,
+    prior_roots: Vec<Slot>,
 }
 
 impl<'a> From<crate::bank::BankFieldsToSerialize<'a>> for SerializableVersionedBank<'a> {
@@ -153,7 +145,6 @@ impl<'a> From<crate::bank::BankFieldsToSerialize<'a>> for SerializableVersionedB
             ns_per_slot: rhs.ns_per_slot,
             genesis_creation_time: rhs.genesis_creation_time,
             slots_per_year: rhs.slots_per_year,
-            unused: u64::default(),
             slot: rhs.slot,
             epoch: rhs.epoch,
             block_height: rhs.block_height,
@@ -166,9 +157,9 @@ impl<'a> From<crate::bank::BankFieldsToSerialize<'a>> for SerializableVersionedB
             epoch_schedule: rhs.epoch_schedule,
             inflation: rhs.inflation,
             stakes: rhs.stakes,
-            unused_accounts: UnusedAccounts::default(),
             epoch_stakes: rhs.epoch_stakes,
             is_delta: rhs.is_delta,
+            prior_roots: rhs.prior_roots,
         }
     }
 }