cfg param max_concurrent_seals

config-live-example.toml

@@ -27,6 +27,8 @@ dry_run_validation_url = "http://localhost:8545"
 
 ignore_cancellable_orders = true
 
+max_concurrent_seals = 4
+
 sbundle_mergeabe_signers = []
 # slot_delta_to_start_submits_ms is usually negative since we start bidding BEFORE the slot start
 # slot_delta_to_start_submits_ms = -5000

crates/rbuilder/src/live_builder/block_output/block_sealing_bidder_factory.rs

@@ -10,8 +10,9 @@ use tracing::error;
 use super::{
     bid_value_source::interfaces::{BidValueObs, BidValueSource},
     bidding::{
-        interfaces::{BiddingService, SlotBidder},
+        interfaces::{BidMaker, BiddingService, SlotBidder},
         parallel_sealer_bid_maker::ParallelSealerBidMaker,
+        sequential_sealer_bid_maker::SequentialSealerBidMaker,
         wallet_balance_watcher::WalletBalanceWatcher,
     },
     relay_submit::BuilderSinkFactory,
@@ -90,17 +91,24 @@ impl UnfinishedBlockBuildingSinkFactory for BlockSealingBidderFactory {
             self.competition_bid_value_source.clone(),
             cancel.clone(),
         );
-        let sealer = ParallelSealerBidMaker::new(
-            self.max_concurrent_seals,
-            Arc::from(finished_block_sink),
-            cancel.clone(),
-        );
+        let sealer: Box<dyn BidMaker + Send + Sync> = if self.max_concurrent_seals == 1 {
+            Box::new(SequentialSealerBidMaker::new(
+                Arc::from(finished_block_sink),
+                cancel.clone(),
+            ))
+        } else {
+            Box::new(ParallelSealerBidMaker::new(
+                self.max_concurrent_seals,
+                Arc::from(finished_block_sink),
+                cancel.clone(),
+            ))
+        };
 
         let slot_bidder: Arc<dyn SlotBidder> = self.bidding_service.create_slot_bidder(
             slot_data.block(),
             slot_data.slot(),
             slot_data.timestamp(),
-            Box::new(sealer),
+            sealer,
             cancel.clone(),
         );
 

crates/rbuilder/src/live_builder/config.rs

@@ -65,8 +65,8 @@ const DEFAULT_SLOT_DELTA_TO_START_SUBMITS: time::Duration = time::Duration::mill
 /// We initialize the wallet with the last full day. This should be enough for any bidder.
 /// On debug I measured this to be < 300ms so it's not big deal.
 pub const WALLET_INIT_HISTORY_SIZE: Duration = Duration::from_secs(60 * 60 * 24);
-/// Number of sealing processes to run in parallel for each builder algorithm.
-pub const SEALING_PROCESSES_PER_BUILDER_ALGORITHM: usize = 2;
+/// 1 is easier for debugging.
+pub const DEFAULT_MAX_CONCURRENT_SEALS: u64 = 1;
 
 /// This example has a single building algorithm cfg but the idea of this enum is to have several builders
 #[derive(Debug, Clone, Deserialize, PartialEq, Eq)]
@@ -117,9 +117,13 @@ pub struct L1Config {
     /// If true all optimistic submissions will be validated on nodes specified in `dry_run_validation_url`
     pub optimistic_prevalidate_optimistic_blocks: bool,
 
-    // See [`SubmissionConfig`]
+    /// See [`SubmissionConfig`]
     slot_delta_to_start_submits_ms: Option<i64>,
 
+    /// How many seals we are going to be doing in parallel.
+    /// Optimal value may change depending on the roothash computation caching strategies.
+    pub max_concurrent_seals: u64,
+
     ///Name kept singular for backwards compatibility
     #[serde_as(deserialize_as = "OneOrMany<EnvOrValue<String>>")]
     pub cl_node_url: Vec<EnvOrValue<String>>,
@@ -138,6 +142,7 @@ impl Default for L1Config {
             optimistic_prevalidate_optimistic_blocks: false,
             slot_delta_to_start_submits_ms: None,
             cl_node_url: vec![EnvOrValue::from("http://127.0.0.1:3500")],
+            max_concurrent_seals: DEFAULT_MAX_CONCURRENT_SEALS,
         }
     }
 }
@@ -302,7 +307,7 @@ impl LiveBuilderConfig for Config {
             sink_sealed_factory,
             Arc::new(NullBidValueSource {}),
             wallet_balance_watcher,
-            SEALING_PROCESSES_PER_BUILDER_ALGORITHM * self.builders.len(),
+            self.l1_config.max_concurrent_seals as usize,
         ));
 
         let payload_event = MevBoostSlotDataGenerator::new(