Remove max block time param

.changelog/unreleased/improvements/3366-remove-max-block-time-param.md

@@ -0,0 +1,2 @@
+- Remove the `max_expected_time_per_block` genesis parameter.
+  ([\#3366](https://github.com/anoma/namada/pull/3366))

.github/workflows/scripts/hermes.txt

@@ -1 +1 @@
-1.8.2-namada-beta11-rc2
+1.8.2-namada-beta12-rc

crates/apps_lib/src/client/rpc.rs

@@ -626,17 +626,6 @@ pub async fn query_protocol_parameters(
         epoch_duration.min_num_of_blocks
     );
 
-    let key = param_storage::get_max_expected_time_per_block_key();
-    let max_block_duration: u64 = query_storage_value(context.client(), &key)
-        .await
-        .expect("Parameter should be defined.");
-    display_line!(
-        context.io(),
-        "{:4}Max. block duration: {}",
-        "",
-        max_block_duration
-    );
-
     let key = param_storage::get_tx_allowlist_storage_key();
     let vp_allowlist: Vec<String> = query_storage_value(context.client(), &key)
         .await

crates/apps_lib/src/config/genesis.rs

@@ -18,7 +18,7 @@ use namada::core::collections::HashMap;
 use namada::core::key::*;
 use namada::core::storage;
 use namada::core::string_encoding::StringEncoded;
-use namada::core::time::{DateTimeUtc, DurationSecs};
+use namada::core::time::DateTimeUtc;
 use namada::core::token::Denomination;
 use namada::governance::parameters::GovernanceParameters;
 use namada::governance::pgf::parameters::PgfParameters;
@@ -297,8 +297,6 @@ pub struct Parameters {
     pub max_block_gas: u64,
     /// Epoch duration
     pub epoch_duration: EpochDuration,
-    /// Maximum expected time per block
-    pub max_expected_time_per_block: DurationSecs,
     /// Allowed validity predicate hashes
     pub vp_allowlist: Vec<String>,
     /// Allowed tx hashes

crates/apps_lib/src/config/genesis/chain.rs

@@ -296,7 +296,6 @@ impl Finalized {
     ) -> namada::ledger::parameters::Parameters {
         let templates::ChainParams {
             min_num_of_blocks,
-            max_expected_time_per_block,
             max_proposal_bytes,
             vp_allowlist,
             tx_allowlist,
@@ -333,16 +332,12 @@ impl Finalized {
             min_duration: namada::core::time::Duration::seconds(min_duration)
                 .into(),
         };
-        let max_expected_time_per_block =
-            namada::core::time::Duration::seconds(max_expected_time_per_block)
-                .into();
         let vp_allowlist = vp_allowlist.unwrap_or_default();
         let tx_allowlist = tx_allowlist.unwrap_or_default();
 
         namada::ledger::parameters::Parameters {
             max_tx_bytes,
             epoch_duration,
-            max_expected_time_per_block,
             vp_allowlist,
             tx_allowlist,
             implicit_vp_code_hash,

crates/apps_lib/src/config/genesis/templates.rs

@@ -265,9 +265,6 @@ pub struct ChainParams<T: TemplateValidation> {
     /// Minimum number of blocks per epoch.
     // NB: u64 only works with values up to i64::MAX with toml-rs!
     pub min_num_of_blocks: u64,
-    /// Maximum duration per block (in seconds).
-    // NB: this is i64 because datetime wants it
-    pub max_expected_time_per_block: i64,
     /// Max payload size, in bytes, for a tx batch proposal.
     ///
     /// Block proposers may never return a `PrepareProposal`
@@ -315,7 +312,6 @@ impl ChainParams<Unvalidated> {
             native_token,
             is_native_token_transferable,
             min_num_of_blocks,
-            max_expected_time_per_block,
             max_proposal_bytes,
             vp_allowlist,
             tx_allowlist,
@@ -361,7 +357,6 @@ impl ChainParams<Unvalidated> {
             native_token,
             is_native_token_transferable,
             min_num_of_blocks,
-            max_expected_time_per_block,
             max_proposal_bytes,
             vp_allowlist,
             tx_allowlist,

crates/core/src/parameters.rs

@@ -32,8 +32,6 @@ pub struct Parameters {
     pub max_tx_bytes: u32,
     /// Epoch duration (read only)
     pub epoch_duration: EpochDuration,
-    /// Maximum expected time per block (read only)
-    pub max_expected_time_per_block: DurationSecs,
     /// Max payload size, in bytes, for a tx batch proposal.
     pub max_proposal_bytes: ProposalBytes,
     /// Max gas for block

crates/core/src/time.rs

@@ -233,6 +233,18 @@ impl Sub<Duration> for DateTimeUtc {
     }
 }
 
+impl Sub<DateTimeUtc> for DateTimeUtc {
+    type Output = DurationSecs;
+
+    #[allow(clippy::arithmetic_side_effects)]
+    fn sub(self, rhs: DateTimeUtc) -> Self::Output {
+        (self.0 - rhs.0)
+            .to_std()
+            .map(DurationSecs::from)
+            .unwrap_or(DurationSecs(0))
+    }
+}
+
 impl BorshSerialize for DateTimeUtc {
     fn serialize<W: std::io::Write>(
         &self,

crates/ibc/src/context/common.rs

@@ -1,7 +1,5 @@
 //! IbcCommonContext implementation for IBC
 
-use core::time::Duration;
-
 use ibc::apps::nft_transfer::types::{PrefixedClassId, TokenId};
 use ibc::clients::tendermint::consensus_state::ConsensusState as TmConsensusState;
 use ibc::clients::tendermint::types::ConsensusState as TmConsensusStateType;
@@ -25,8 +23,6 @@ use ibc::primitives::Timestamp;
 use namada_core::address::Address;
 use namada_core::storage::{BlockHeight, Key};
 use namada_core::tendermint::Time as TmTime;
-use namada_core::time::DurationSecs;
-use namada_parameters::storage::get_max_expected_time_per_block_key;
 use namada_token::storage_key::balance_key;
 use namada_token::Amount;
 use prost::Message;
@@ -327,15 +323,6 @@ pub trait IbcCommonContext: IbcStorageContext {
         Ok(consensus_state.into())
     }
 
-    /// Get the max expected time per block
-    fn max_expected_time_per_block(&self) -> Result<Duration> {
-        let key = get_max_expected_time_per_block_key();
-        match self.read::<DurationSecs>(&key)? {
-            Some(duration) => Ok(duration.into()),
-            None => unreachable!("The parameter should be initialized"),
-        }
-    }
-
     /// Get the ConnectionEnd
     fn connection_end(&self, conn_id: &ConnectionId) -> Result<ConnectionEnd> {
         let key = storage::connection_key(conn_id);

crates/ibc/src/context/validation.rs

@@ -263,10 +263,28 @@ where
     }
 
     fn max_expected_time_per_block(&self) -> core::time::Duration {
-        self.inner
+        let height = self
+            .inner
             .borrow()
-            .max_expected_time_per_block()
-            .expect("Error cannot be returned")
+            .get_block_height()
+            .expect("The height should exist");
+
+        let estimate =
+            namada_parameters::estimate_max_block_time_from_blocks_and_params(
+                &*self.inner.borrow(),
+                height,
+                // NB: estimate max height with up to 5 blocks in the past,
+                // which will not result in too many reads
+                5,
+            )
+            .expect("Failed to estimate max block time");
+
+        // NB: pick a lower max blocktime estimate during tests,
+        // to avoid flakes in CI
+        #[cfg(any(test, feature = "testing"))]
+        let estimate = estimate.min(namada_core::time::DurationSecs(5));
+
+        estimate.into()
     }
 
     fn validate_message_signer(

crates/namada/src/ledger/native_vp/ibc/mod.rs

@@ -518,9 +518,7 @@ mod tests {
     use crate::ibc::{MsgNftTransfer, MsgTransfer, NftClass, NftMetadata};
     use crate::key::testing::keypair_1;
     use crate::ledger::gas::VpGasMeter;
-    use crate::ledger::parameters::storage::{
-        get_epoch_duration_storage_key, get_max_expected_time_per_block_key,
-    };
+    use crate::ledger::parameters::storage::get_epoch_duration_storage_key;
     use crate::ledger::parameters::EpochDuration;
     use crate::ledger::{ibc, pos};
     use crate::storage::{BlockHeight, TxIndex};
@@ -567,13 +565,6 @@ mod tests {
             .write_log_mut()
             .write(&epoch_duration_key, epoch_duration.serialize_to_vec())
             .expect("write failed");
-        // max_expected_time_per_block
-        let time = DurationSecs::from(Duration::new(60, 0));
-        let time_key = get_max_expected_time_per_block_key();
-        state
-            .write_log_mut()
-            .write(&time_key, namada_core::encode(&time))
-            .expect("write failed");
         // set a dummy header
         state
             .in_mem_mut()

crates/node/src/storage/mod.rs

@@ -166,7 +166,6 @@ mod tests {
                 min_num_of_blocks: 1,
                 min_duration: DurationSecs(3600),
             },
-            max_expected_time_per_block: DurationSecs(3600),
             max_proposal_bytes: Default::default(),
             max_block_gas: 100,
             vp_allowlist: vec![],

crates/parameters/Cargo.toml

@@ -24,4 +24,8 @@ namada_core = { path = "../core" }
 namada_macros = { path = "../macros" }
 namada_storage = { path = "../storage" }
 
+smooth-operator.workspace = true
 thiserror.workspace = true
+
+[dev-dependencies]
+namada_storage = { path = "../storage", features = ["testing"] }