From 52dee5ee91d64f06bb00c4fff6e3a52b0430054e Mon Sep 17 00:00:00 2001
From: Sergey Kroshnin <sergiysw@gmail.com>
Date: Wed, 6 Nov 2019 23:01:44 +0300
Subject: [PATCH] Limit max lazy bootstrap blocks size if legacy bootstrap is
 enabled

1M lazy blocks limit
---
 nano/node/bootstrap/bootstrap.cpp | 26 ++++++++++++++++++++++----
 nano/node/bootstrap/bootstrap.hpp |  4 ++++
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/nano/node/bootstrap/bootstrap.cpp b/nano/node/bootstrap/bootstrap.cpp
index 9df1f7392..be333fe5f 100644
--- a/nano/node/bootstrap/bootstrap.cpp
+++ b/nano/node/bootstrap/bootstrap.cpp
@@ -25,6 +25,7 @@ constexpr std::chrono::seconds nano::bootstrap_limits::lazy_flush_delay_sec;
 constexpr unsigned nano::bootstrap_limits::lazy_destinations_request_limit;
 constexpr uint64_t nano::bootstrap_limits::lazy_batch_pull_count_resize_blocks_limit;
 constexpr double nano::bootstrap_limits::lazy_batch_pull_count_resize_ratio;
+constexpr size_t nano::bootstrap_limits::lazy_blocks_restart_limit;
 constexpr std::chrono::hours nano::bootstrap_excluded_peers::exclude_time_hours;
 constexpr std::chrono::hours nano::bootstrap_excluded_peers::exclude_remove_hours;
 
@@ -890,10 +891,27 @@ bool nano::bootstrap_attempt::lazy_finished ()
 	return result;
 }
 
+bool nano::bootstrap_attempt::lazy_has_expired () const
+{
+	bool result (false);
+	// Max 30 minutes run with enabled legacy bootstrap
+	static std::chrono::minutes const max_lazy_time (node->flags.disable_legacy_bootstrap ? 7 * 24 * 60 : 30);
+	if (std::chrono::steady_clock::now () - lazy_start_time >= max_lazy_time)
+	{
+		result = true;
+	}
+	else if (!node->flags.disable_legacy_bootstrap && lazy_blocks_count > nano::bootstrap_limits::lazy_blocks_restart_limit)
+	{
+		result = true;
+	}
+	return result;
+}
+
 void nano::bootstrap_attempt::lazy_clear ()
 {
 	assert (!lazy_mutex.try_lock ());
 	lazy_blocks.clear ();
+	lazy_blocks_count = 0;
 	lazy_keys.clear ();
 	lazy_pulls.clear ();
 	lazy_state_backlog.clear ();
@@ -905,13 +923,12 @@ void nano::bootstrap_attempt::lazy_run ()
 {
 	assert (!node->flags.disable_lazy_bootstrap);
 	start_populate_connections ();
-	auto start_time (std::chrono::steady_clock::now ());
-	auto max_time (std::chrono::minutes (node->flags.disable_legacy_bootstrap ? 7 * 24 * 60 : 30));
+	lazy_start_time = std::chrono::steady_clock::now ();
 	nano::unique_lock<std::mutex> lock (mutex);
-	while ((still_pulling () || !lazy_finished ()) && std::chrono::steady_clock::now () - start_time < max_time)
+	while ((still_pulling () || !lazy_finished ()) && !lazy_has_expired ())
 	{
 		unsigned iterations (0);
-		while (still_pulling () && std::chrono::steady_clock::now () - start_time < max_time)
+		while (still_pulling () && !lazy_has_expired ())
 		{
 			if (!pulls.empty ())
 			{
@@ -1030,6 +1047,7 @@ bool nano::bootstrap_attempt::process_block_lazy (std::shared_ptr<nano::block> b
 			}
 		}
 		lazy_blocks.insert (hash);
+		++lazy_blocks_count;
 		// Adding lazy balances for first processed block in pull
 		if (pull_blocks == 0 && (block_a->type () == nano::block_type::state || block_a->type () == nano::block_type::send))
 		{
diff --git a/nano/node/bootstrap/bootstrap.hpp b/nano/node/bootstrap/bootstrap.hpp
index 3b3125929..459def3d6 100644
--- a/nano/node/bootstrap/bootstrap.hpp
+++ b/nano/node/bootstrap/bootstrap.hpp
@@ -89,6 +89,7 @@ public:
 	void lazy_add (nano::hash_or_account const &, unsigned = std::numeric_limits<unsigned>::max ());
 	void lazy_requeue (nano::block_hash const &, nano::block_hash const &, bool);
 	bool lazy_finished ();
+	bool lazy_has_expired () const;
 	void lazy_pull_flush ();
 	void lazy_clear ();
 	bool process_block_lazy (std::shared_ptr<nano::block>, nano::account const &, uint64_t, nano::bulk_pull::count_t, unsigned);
@@ -139,6 +140,7 @@ public:
 	std::unordered_map<nano::block_hash, nano::uint128_t> lazy_balances;
 	std::unordered_set<nano::block_hash> lazy_keys;
 	std::deque<std::pair<nano::hash_or_account, unsigned>> lazy_pulls;
+	std::chrono::steady_clock::time_point lazy_start_time;
 	std::chrono::steady_clock::time_point last_lazy_flush{ std::chrono::steady_clock::now () };
 	class account_tag
 	{
@@ -152,6 +154,7 @@ public:
 	boost::multi_index::ordered_non_unique<boost::multi_index::tag<count_tag>, boost::multi_index::member<lazy_destinations_item, uint64_t, &lazy_destinations_item::count>, std::greater<uint64_t>>,
 	boost::multi_index::hashed_unique<boost::multi_index::tag<account_tag>, boost::multi_index::member<lazy_destinations_item, nano::account, &lazy_destinations_item::account>>>>
 	lazy_destinations;
+	std::atomic<size_t> lazy_blocks_count{ 0 };
 	std::atomic<bool> lazy_destinations_flushed{ false };
 	std::mutex lazy_mutex;
 	// Wallet lazy bootstrap
@@ -284,5 +287,6 @@ public:
 	static constexpr unsigned lazy_destinations_request_limit = 256 * 1024;
 	static constexpr uint64_t lazy_batch_pull_count_resize_blocks_limit = 4 * 1024 * 1024;
 	static constexpr double lazy_batch_pull_count_resize_ratio = 2.0;
+	static constexpr size_t lazy_blocks_restart_limit = 1024 * 1024;
 };
 }