chore: improve error message

resource/ckb.toml

@@ -133,7 +133,7 @@ enable_deprecated_rpc = false # {{
 
 [tx_pool]
 max_tx_pool_size = 180_000_000 # 180mb
-min_fee_rate = 1_000 # shannons/KB
+min_fee_rate = 1_000 # Here fee_rate are calculated directly using size in units of shannons/KB
 max_tx_verify_cycles = 70_000_000
 max_ancestors_count = 25
 

rpc/src/tests/error.rs

@@ -22,7 +22,7 @@ fn test_submit_transaction_error() {
     let min_fee_rate = FeeRate::from_u64(500);
     let reject = Reject::LowFeeRate(min_fee_rate, 100, 50);
     assert_eq!(
-            "PoolRejectedTransactionByMinFeeRate: The min fee rate is 500 shannons/KB, so the transaction fee should be 100 shannons at least, but only got 50",
+            "PoolRejectedTransactionByMinFeeRate: The min fee rate is 500 shannons/KW, so the transaction fee should be 100 shannons at least, but only got 50",
             RPCError::from_submit_transaction_reject(&reject).message
         );
 
@@ -32,9 +32,12 @@ fn test_submit_transaction_error() {
             RPCError::from_submit_transaction_reject(&reject).message
         );
 
-    let reject = Reject::Full("size".to_owned());
+    let reject = Reject::Full(format!(
+        "the fee_rate for this transaction is: {}",
+        FeeRate::from_u64(500)
+    ));
     assert_eq!(
-        "PoolIsFull: Transaction are replaced because the pool is full size",
+        "PoolIsFull: Transaction are replaced because the pool is full, the fee_rate for this transaction is: 500 shannons/KW",
         RPCError::from_submit_transaction_reject(&reject).message
     );
 

test/src/specs/relay/transaction_relay_low_fee_rate.rs

@@ -36,7 +36,7 @@ impl Spec for TransactionRelayLowFeeRate {
             node1,
             0,
             10,
-            "reject tx The min fee rate is 1000 shannons/KB, so the transaction fee should be 242 shannons at least, but only got 0"
+            "reject tx The min fee rate is 1000 shannons/KW, so the transaction fee should be 242 shannons at least, but only got 0"
         )
         .is_some());
     }

test/template/ckb.toml

@@ -78,8 +78,7 @@ enable_deprecated_rpc = true
 
 [tx_pool]
 max_tx_pool_size = 180_000_000 # 180mb
-max_cycles = 200_000_000_000
-min_fee_rate = 0 # shannons/KB
+min_fee_rate = 0 # Here fee_rate are calculated directly using size in units of shannons/KB
 max_tx_verify_cycles = 70_000_000
 max_ancestors_count = 25
 

tx-pool/src/component/entry.rs

@@ -98,6 +98,12 @@ impl TxEntry {
         EvictKey::from(self)
     }
 
+    /// Returns fee rate
+    pub fn fee_rate(&self) -> FeeRate {
+        let weight = get_transaction_weight(self.size, self.cycles);
+        FeeRate::calculate(self.fee, weight)
+    }
+
     /// Update ancestor state for add an entry
     pub fn add_entry_weight(&mut self, entry: &TxEntry) {
         self.ancestors_count = self.ancestors_count.saturating_add(1);
@@ -183,9 +189,10 @@ impl Ord for TxEntry {
 }
 
 /// Currently we do not have trace descendants,
-/// so we take the simplest strategy to evict the transactions by first comparing the fee_rate,
-/// and then taking the one with the largest timestamp,
-/// which also means that the fewer descendants may exist.
+/// so first take the simplest strategy,
+/// first compare fee_rate, select the smallest fee_rate,
+/// and then select the latest timestamp, for eviction,
+/// the latest timestamp which also means that the fewer descendants may exist.
 #[derive(Eq, PartialEq, Clone, Debug)]
 pub struct EvictKey {
     fee_rate: FeeRate,
@@ -194,9 +201,8 @@ pub struct EvictKey {
 
 impl From<&TxEntry> for EvictKey {
     fn from(entry: &TxEntry) -> Self {
-        let weight = get_transaction_weight(entry.size, entry.cycles);
         EvictKey {
-            fee_rate: FeeRate::calculate(entry.fee, weight),
+            fee_rate: entry.fee_rate(),
             timestamp: entry.timestamp,
         }
     }

tx-pool/src/pool.rs

@@ -42,7 +42,10 @@ macro_rules! evict_for_trim_size {
                     "removed by size limit {} timestamp({})",
                     tx_hash, entry.timestamp
                 );
-                let reject = Reject::Full(format!("fee: {}", entry.fee));
+                let reject = Reject::Full(format!(
+                    "the fee_rate for this transaction is: {}",
+                    entry.fee_rate()
+                ));
                 $callbacks.call_reject($self, &entry, reject);
             }
         }

tx-pool/src/process.rs

@@ -941,7 +941,7 @@ fn _update_tx_pool_for_reorg(
     // Remove expired transaction from pending
     tx_pool.remove_expired(callbacks);
 
-    // Remove transactions from the pool until its size < size_limit.
+    // Remove transactions from the pool until its size <= size_limit.
     tx_pool.limit_size(callbacks);
 }
 

util/types/src/core/fee_rate.rs

@@ -39,6 +39,6 @@ impl FeeRate {
 
 impl ::std::fmt::Display for FeeRate {
     fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
-        write!(f, "{}", self.0)
+        write!(f, "{} shannons/KW", self.0)
     }
 }

util/types/src/core/tx_pool.rs

@@ -14,7 +14,7 @@ use std::collections::HashMap;
 #[derive(Error, Debug, Clone)]
 pub enum Reject {
     /// Transaction fee lower than config
-    #[error("The min fee rate is {0} shannons/KB, so the transaction fee should be {1} shannons at least, but only got {2}")]
+    #[error("The min fee rate is {0}, so the transaction fee should be {1} shannons at least, but only got {2}")]
     LowFeeRate(FeeRate, u64, u64),
 
     /// Transaction exceeded maximum ancestors count limit
@@ -26,7 +26,7 @@ pub enum Reject {
     ExceededTransactionSizeLimit(u64, u64),
 
     /// Transaction are replaced because the pool is full
-    #[error("Transaction are replaced because the pool is full {0}")]
+    #[error("Transaction are replaced because the pool is full, {0}")]
     Full(String),
 
     /// Transaction already exist in transaction_pool