Offload block activation to background workers

nano/lib/stats_enums.hpp

@@ -380,6 +380,8 @@ enum class detail
 	// active
 	insert,
 	insert_failed,
+	activate_account,
+	activate_destination,
 
 	// active_elections
 	started,

nano/lib/thread_roles.cpp

@@ -154,6 +154,9 @@ std::string nano::thread_role::get_string (nano::thread_role::name role)
 		case nano::thread_role::name::vote_router:
 			thread_role_name_string = "Vote router";
 			break;
+		case nano::thread_role::name::successor_activation:
+			thread_role_name_string = "Successor actv";
+			break;
 		default:
 			debug_assert (false && "nano::thread_role::get_string unhandled thread role");
 	}

nano/lib/thread_roles.hpp

@@ -58,6 +58,7 @@ enum class name
 	port_mapping,
 	stats,
 	vote_router,
+	successor_activation,
 };
 
 std::string_view to_string (name);

nano/node/active_elections.cpp

@@ -26,6 +26,7 @@ nano::active_elections::active_elections (nano::node & node_a, nano::confirming_
 	block_processor{ block_processor_a },
 	recently_confirmed{ config.confirmation_cache },
 	recently_cemented{ config.confirmation_history_size },
+	activate_workers{ 1, nano::thread_role::name::successor_activation }, // TODO: Make threads configurable
 	election_time_to_live{ node_a.network_params.network.is_dev_network () ? 0s : 2s }
 {
 	count_by_behavior.fill (0); // Zero initialize array
@@ -87,6 +88,7 @@ void nano::active_elections::stop ()
 		stopped = true;
 	}
 	condition.notify_all ();
+	activate_workers.stop ();
 	nano::join_or_pass (thread);
 	clear ();
 }
@@ -134,7 +136,9 @@ void nano::active_elections::block_cemented_callback (nano::secure::transaction
 	// Next-block activations are only done for blocks with previously active elections
 	if (cemented_bootstrap_count_reached && was_active && !node.flags.disable_activate_successors)
 	{
-		activate_successors (transaction, block);
+		activate_workers.push_task ([this, block = block] () {
+			activate_successors (node.ledger.tx_begin_read (), block);
+		});
 	}
 }
 
@@ -175,11 +179,13 @@ void nano::active_elections::notify_observers (nano::secure::transaction const &
 
 void nano::active_elections::activate_successors (nano::secure::transaction const & transaction, std::shared_ptr<nano::block> const & block)
 {
+	node.stats.inc (nano::stat::type::active, nano::stat::detail::activate_account);
 	node.scheduler.priority.activate (transaction, block->account ());
 
 	// Start or vote for the next unconfirmed block in the destination account
 	if (block->is_send () && !block->destination ().is_zero () && block->destination () != block->account ())
 	{
+		node.stats.inc (nano::stat::type::active, nano::stat::detail::activate_destination);
 		node.scheduler.priority.activate (transaction, block->destination ());
 	}
 }
@@ -566,6 +572,8 @@ std::unique_ptr<nano::container_info_component> nano::collect_container_info (ac
 	composite->add_component (active_elections.recently_confirmed.collect_container_info ("recently_confirmed"));
 	composite->add_component (active_elections.recently_cemented.collect_container_info ("recently_cemented"));
 
+	composite->add_component (active_elections.activate_workers.collect_container_info ("activate_workers"));
+
 	return composite;
 }
 

nano/node/active_elections.hpp

@@ -2,6 +2,7 @@
 
 #include <nano/lib/enum_util.hpp>
 #include <nano/lib/numbers.hpp>
+#include <nano/lib/thread_pool.hpp>
 #include <nano/node/election_behavior.hpp>
 #include <nano/node/election_insertion_result.hpp>
 #include <nano/node/election_status.hpp>
@@ -157,14 +158,16 @@ class active_elections final
 	nano::block_processor & block_processor;
 
 public:
-	recently_confirmed_cache recently_confirmed;
-	recently_cemented_cache recently_cemented;
+	nano::recently_confirmed_cache recently_confirmed;
+	nano::recently_cemented_cache recently_cemented;
 
 	// TODO: This mutex is currently public because many tests access it
 	// TODO: This is bad. Remove the need to explicitly lock this from any code outside of this class
 	mutable nano::mutex mutex{ mutex_identifier (mutexes::active) };
 
 private:
+	nano::thread_pool activate_workers;
+
 	nano::mutex election_winner_details_mutex{ mutex_identifier (mutexes::election_winner_details) };
 	std::unordered_map<nano::block_hash, std::shared_ptr<nano::election>> election_winner_details;