Submit a vote timestamp every vote (#10630)

* Submit a timestamp for every vote

* Submit at most one vote timestamp per second

* Submit a timestamp for every new vote

Co-authored-by: Tyera Eulberg <tyera@solana.com>

core/src/consensus.rs

@@ -13,9 +13,7 @@ use solana_sdk::{
 };
 use solana_vote_program::{
     vote_instruction,
-    vote_state::{
-        BlockTimestamp, Lockout, Vote, VoteState, MAX_LOCKOUT_HISTORY, TIMESTAMP_SLOT_INTERVAL,
-    },
+    vote_state::{BlockTimestamp, Lockout, Vote, VoteState, MAX_LOCKOUT_HISTORY},
 };
 use std::{
     collections::{BTreeMap, HashMap, HashSet},
@@ -345,6 +343,20 @@ impl Tower {
         last_vote
     }
 
+    fn maybe_timestamp(&mut self, current_slot: Slot) -> Option<UnixTimestamp> {
+        if current_slot > self.last_timestamp.slot {
+            let timestamp = Utc::now().timestamp();
+            if timestamp >= self.last_timestamp.timestamp {
+                self.last_timestamp = BlockTimestamp {
+                    slot: current_slot,
+                    timestamp,
+                };
+                return Some(timestamp);
+            }
+        }
+        None
+    }
+
     pub fn root(&self) -> Option<Slot> {
         self.lockouts.root_slot
     }
@@ -650,21 +662,6 @@ impl Tower {
             );
         }
     }
-
-    fn maybe_timestamp(&mut self, current_slot: Slot) -> Option<UnixTimestamp> {
-        if self.last_timestamp.slot == 0
-            || self.last_timestamp.slot < (current_slot - (current_slot % TIMESTAMP_SLOT_INTERVAL))
-        {
-            let timestamp = Utc::now().timestamp();
-            self.last_timestamp = BlockTimestamp {
-                slot: current_slot,
-                timestamp,
-            };
-            Some(timestamp)
-        } else {
-            None
-        }
-    }
 }
 
 #[cfg(test)]
@@ -691,12 +688,7 @@ pub mod test {
         vote_state::{Vote, VoteStateVersions, MAX_LOCKOUT_HISTORY},
         vote_transaction,
     };
-    use std::{
-        collections::HashMap,
-        rc::Rc,
-        sync::RwLock,
-        {thread::sleep, time::Duration},
-    };
+    use std::{collections::HashMap, rc::Rc, sync::RwLock};
     use trees::{tr, Tree, TreeWalk};
 
     pub(crate) struct VoteSimulator {
@@ -1829,17 +1821,15 @@ pub mod test {
     #[test]
     fn test_maybe_timestamp() {
         let mut tower = Tower::default();
-        assert!(tower.maybe_timestamp(TIMESTAMP_SLOT_INTERVAL).is_some());
-        let BlockTimestamp { slot, timestamp } = tower.last_timestamp;
+        assert!(tower.maybe_timestamp(0).is_none());
+        assert!(tower.maybe_timestamp(1).is_some());
+        assert!(tower.maybe_timestamp(0).is_none()); // Refuse to timestamp an older slot
+        assert!(tower.maybe_timestamp(1).is_none()); // Refuse to timestamp the same slot twice
 
-        assert_eq!(tower.maybe_timestamp(1), None);
-        assert_eq!(tower.maybe_timestamp(slot), None);
-        assert_eq!(tower.maybe_timestamp(slot + 1), None);
+        tower.last_timestamp.timestamp -= 1; // Move last_timestamp into the past
+        assert!(tower.maybe_timestamp(2).is_some()); // slot 2 gets a timestamp
 
-        sleep(Duration::from_secs(1));
-        assert!(tower
-            .maybe_timestamp(slot + TIMESTAMP_SLOT_INTERVAL + 1)
-            .is_some());
-        assert!(tower.last_timestamp.timestamp > timestamp);
+        tower.last_timestamp.timestamp += 1_000_000; // Move last_timestamp well into the future
+        assert!(tower.maybe_timestamp(3).is_none()); // slot 3 gets no timestamp
     }
 }

core/src/rpc_error.rs

@@ -46,7 +46,7 @@ impl From<RpcCustomError> for Error {
             },
             RpcCustomError::BlockNotAvailable { slot } => Self {
                 code: ErrorCode::ServerError(JSON_RPC_SERVER_ERROR_4),
-                message: format!("Block not available for slot {}", slot,),
+                message: format!("Block not available for slot {}", slot),
                 data: None,
             },
         }

ledger/src/blockstore.rs

@@ -41,7 +41,7 @@ use solana_transaction_status::{
     EncodedTransaction, Rewards, TransactionStatusMeta, TransactionWithStatusMeta,
     UiTransactionEncoding, UiTransactionStatusMeta,
 };
-use solana_vote_program::{vote_instruction::VoteInstruction, vote_state::TIMESTAMP_SLOT_INTERVAL};
+use solana_vote_program::vote_instruction::VoteInstruction;
 use std::{
     cell::RefCell,
     cmp,
@@ -78,6 +78,7 @@ thread_local!(static PAR_THREAD_POOL_ALL_CPUS: RefCell<ThreadPool> = RefCell::ne
 pub const MAX_COMPLETED_SLOTS_IN_CHANNEL: usize = 100_000;
 pub const MAX_TURBINE_PROPAGATION_IN_MS: u64 = 100;
 pub const MAX_TURBINE_DELAY_IN_TICKS: u64 = MAX_TURBINE_PROPAGATION_IN_MS / MS_PER_TICK;
+const TIMESTAMP_SLOT_INTERVAL: u64 = 4500;
 const TIMESTAMP_SLOT_RANGE: usize = 16;
 
 // An upper bound on maximum number of data shreds we can handle in a slot

programs/vote/src/vote_state/mod.rs

@@ -32,10 +32,6 @@ pub const INITIAL_LOCKOUT: usize = 2;
 //  smaller numbers makes
 pub const MAX_EPOCH_CREDITS_HISTORY: usize = 64;
 
-// Frequency of timestamp Votes. In v0.22.0, this is approximately 30min with cluster clock
-// defaults, intended to limit block time drift to < 1hr
-pub const TIMESTAMP_SLOT_INTERVAL: u64 = 4500;
-
 #[frozen_abi(digest = "69hYtmmcuqPbhpc64ZaNJDidaUcg66CW6wzPFiuYZ3To")]
 #[derive(Serialize, Default, Deserialize, Debug, PartialEq, Eq, Clone, AbiExample)]
 pub struct Vote {