diff --git a/ChangeLog b/ChangeLog
index 060a3879d..ccbd4d0e6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -88,6 +88,8 @@
 	* resume data no longer has timestamps of files
 	* require C++11 to build libtorrent
 
+	* improve connect-boost feature, to make new torrents quickly connect peers
+
 1.1.9 release
 
 	* save both file and piece priorities in resume file
diff --git a/include/libtorrent/settings_pack.hpp b/include/libtorrent/settings_pack.hpp
index e762f941b..914a91d47 100644
--- a/include/libtorrent/settings_pack.hpp
+++ b/include/libtorrent/settings_pack.hpp
@@ -1444,6 +1444,7 @@ namespace libtorrent {
 			// them starting up. The normal connect scheduler is run once every
 			// second, this allows peers to be connected immediately instead of
 			// waiting for the session tick to trigger connections.
+			// This may not be set higher than 255.
 			torrent_connect_boost,
 
 			// ``alert_queue_size`` is the maximum number of alerts queued up
diff --git a/include/libtorrent/torrent.hpp b/include/libtorrent/torrent.hpp
index 8e6bc2aa6..2ca975db1 100644
--- a/include/libtorrent/torrent.hpp
+++ b/include/libtorrent/torrent.hpp
@@ -1568,13 +1568,6 @@ namespace libtorrent {
 
 		// 1 bit here
 
-		// this is set to true when the torrent starts up
-		// The first tracker response, when this is true,
-		// will attempt to connect to a bunch of peers immediately
-		// and set this to false. We only do this once to get
-		// the torrent kick-started
-		bool m_need_connect_boost:1;
-
 		// rotating sequence number for LSD announces sent out.
 		// used to only use IP broadcast for every 8th lsd announce
 		std::uint8_t m_lsd_seq:3;
@@ -1601,7 +1594,14 @@ namespace libtorrent {
 		// the number of bytes of padding files
 		std::uint32_t m_padding:24;
 
-		// TODO: gap of 8 bits available here
+		// this is set to the connect boost quota for this torrent.
+		// After having received this many priority peer connection attempts, it
+		// falls back onto the steady state peer connection logic, driven by the
+		// session tick. Each tracker response, as long as this is non-zero, will
+		// attempt to connect to peers immediately and decrement the counter.
+		// We give torrents a connect boost when they are first added and then
+		// every time they resume from being paused.
+		std::uint8_t m_connect_boost_counter;
 
 // ----
 
diff --git a/include/libtorrent/torrent_flags.hpp b/include/libtorrent/torrent_flags.hpp
index 7dc7c85e1..d078bd1a3 100644
--- a/include/libtorrent/torrent_flags.hpp
+++ b/include/libtorrent/torrent_flags.hpp
@@ -175,6 +175,11 @@ namespace torrent_flags {
 	// for the state_changed_alert and then call pause(). The download/seeding
 	// will most likely start in between posting the alert and receiving the
 	// call to pause.
+	//
+	// A downloading state is one where peers are being connected. Which means
+	// just downloading the metadata via the ``ut_metadata`` extension counts
+	// as a downloading state. In order to stop a torrent once the metadata
+	// has been downloaded, instead set all file priorities to dont_download
 	constexpr torrent_flags_t stop_when_ready = 10_bit;
 
 	// when this flag is set, the tracker list in the add_torrent_params
diff --git a/include/libtorrent/torrent_handle.hpp b/include/libtorrent/torrent_handle.hpp
index 34520656b..86cf0a922 100644
--- a/include/libtorrent/torrent_handle.hpp
+++ b/include/libtorrent/torrent_handle.hpp
@@ -689,9 +689,8 @@ TORRENT_IPV6_NAMESPACE_END
 		//	extern int outstanding_resume_data; // global counter of outstanding resume data
 		//	std::vector<torrent_handle> handles = ses.get_torrents();
 		//	ses.pause();
-		//	for (torrent_handle i : handles)
+		//	for (torrent_handle const& h : handles)
 		//	{
-		//		torrent_handle& h = *i;
 		//		if (!h.is_valid()) continue;
 		//		torrent_status s = h.status();
 		//		if (!s.has_metadata || !s.need_save_resume_data()) continue;
@@ -705,7 +704,7 @@ TORRENT_IPV6_NAMESPACE_END
 		//		alert const* a = ses.wait_for_alert(seconds(10));
 		//
 		//		// if we don't get an alert within 10 seconds, abort
-		//		if (a == 0) break;
+		//		if (a == nullptr) break;
 		//
 		//		std::vector<alert*> alerts;
 		//		ses.pop_alerts(&alerts);
@@ -720,7 +719,7 @@ TORRENT_IPV6_NAMESPACE_END
 		//			}
 		//
 		//			save_resume_data_alert const* rd = alert_cast<save_resume_data_alert>(a);
-		//			if (rd == 0)
+		//			if (rd == nullptr)
 		//			{
 		//				process_alert(a);
 		//				continue;
@@ -754,9 +753,10 @@ TORRENT_IPV6_NAMESPACE_END
 		// time.
 		//
 		//.. note::
-		//	A torrent's resume data is considered saved as soon as the alert is
-		//	posted. It is important to make sure this alert is received and
-		//	handled in order for this function to be meaningful.
+		//	A torrent's resume data is considered saved as soon as the
+		//	save_resume_data_alert is posted. It is important to make sure this
+		//	alert is received and handled in order for this function to be
+		//	meaningful.
 		bool need_save_resume_data() const;
 
 		// Every torrent that is added is assigned a queue position exactly one
diff --git a/simulation/test_swarm.cpp b/simulation/test_swarm.cpp
index 6e0bd2b42..7f2f85518 100644
--- a/simulation/test_swarm.cpp
+++ b/simulation/test_swarm.cpp
@@ -299,7 +299,7 @@ void test_stop_start_download(swarm_test type, bool graceful)
 
 			std::printf("tick: %d\n", ticks);
 
-			const int timeout = type == swarm_test::download ? 20 : 100;
+			const int timeout = type == swarm_test::download ? 21 : 100;
 			if (ticks > timeout)
 			{
 				TEST_ERROR("timeout");
diff --git a/src/session.cpp b/src/session.cpp
index ab733aa05..b02fcaedb 100644
--- a/src/session.cpp
+++ b/src/session.cpp
@@ -275,9 +275,7 @@ namespace {
 		// number of disk threads for low level file operations
 		set.set_int(settings_pack::aio_threads, 8);
 
-		// keep 5 MiB outstanding when checking hashes
-		// of a resumed file
-		set.set_int(settings_pack::checking_mem_usage, 320);
+		set.set_int(settings_pack::checking_mem_usage, 2048);
 
 		return set;
 	}
diff --git a/src/session_impl.cpp b/src/session_impl.cpp
index cf9e09522..aa0dead96 100644
--- a/src/session_impl.cpp
+++ b/src/session_impl.cpp
@@ -4085,16 +4085,14 @@ namespace aux {
 		// attempt this tick
 		int max_connections = m_settings.get_int(settings_pack::connection_speed);
 
-		// zero connections speeds are allowed, we just won't make any connections
-		if (max_connections <= 0) return;
-
 		// this loop will "hand out" connection_speed to the torrents, in a round
 		// robin fashion, so that every torrent is equally likely to connect to a
 		// peer
 
 		// boost connections are connections made by torrent connection
 		// boost, which are done immediately on a tracker response. These
-		// connections needs to be deducted from this second
+		// connections needs to be deducted from the regular connection attempt
+		// quota for this tick
 		if (m_boost_connections > 0)
 		{
 			if (m_boost_connections > max_connections)
@@ -4109,6 +4107,9 @@ namespace aux {
 			}
 		}
 
+		// zero connections speeds are allowed, we just won't make any connections
+		if (max_connections <= 0) return;
+
 		// TODO: use a lower limit than m_settings.connections_limit
 		// to allocate the to 10% or so of connection slots for incoming
 		// connections
diff --git a/src/settings_pack.cpp b/src/settings_pack.cpp
index 0df55d41a..414ca52f2 100644
--- a/src/settings_pack.cpp
+++ b/src/settings_pack.cpp
@@ -233,7 +233,7 @@ constexpr int CLOSE_FILE_INTERVAL = 0;
 		SET(max_failcount, 3, &session_impl::update_max_failcount),
 		SET(min_reconnect_time, 60, nullptr),
 		SET(peer_connect_timeout, 15, nullptr),
-		SET(connection_speed, 10, &session_impl::update_connection_speed),
+		SET(connection_speed, 30, &session_impl::update_connection_speed),
 		SET(inactivity_timeout, 600, nullptr),
 		SET(unchoke_interval, 15, nullptr),
 		SET(optimistic_unchoke_interval, 30, nullptr),
@@ -313,7 +313,7 @@ constexpr int CLOSE_FILE_INTERVAL = 0;
 		SET(utp_loss_multiplier, 50, nullptr),
 		SET(mixed_mode_algorithm, settings_pack::peer_proportional, nullptr),
 		SET(listen_queue_size, 5, nullptr),
-		SET(torrent_connect_boost, 10, nullptr),
+		SET(torrent_connect_boost, 80, nullptr),
 		SET(alert_queue_size, 1000, &session_impl::update_alert_queue_size),
 		SET(max_metadata_size, 3 * 1024 * 10240, nullptr),
 		DEPRECATED_SET(hashing_threads, 1, nullptr),
diff --git a/src/storage.cpp b/src/storage.cpp
index 40eaa4e5e..692d49579 100644
--- a/src/storage.cpp
+++ b/src/storage.cpp
@@ -139,7 +139,7 @@ namespace libtorrent {
 					return;
 				}
 
-				if (m_part_file)
+				if (m_part_file && use_partfile(i))
 				{
 					m_part_file->export_file([&f, &ec](std::int64_t file_offset, span<char> buf)
 					{
diff --git a/src/torrent.cpp b/src/torrent.cpp
index da36bd584..d26833863 100644
--- a/src/torrent.cpp
+++ b/src/torrent.cpp
@@ -207,12 +207,12 @@ bool is_downloading_state(int const st)
 		, m_max_uploads((1 << 24) - 1)
 		, m_save_resume_flags()
 		, m_num_uploads(0)
-		, m_need_connect_boost(true)
 		, m_lsd_seq(0)
 		, m_magnet_link(false)
 		, m_apply_ip_filter(p.flags & torrent_flags::apply_ip_filter)
 		, m_pending_active_change(false)
 		, m_padding(0)
+		, m_connect_boost_counter(static_cast<std::uint8_t>(settings().get_int(settings_pack::torrent_connect_boost)))
 		, m_incomplete(0xffffff)
 		, m_announce_to_dht(!(p.flags & torrent_flags::paused))
 		, m_ssl_torrent(false)
@@ -3267,23 +3267,24 @@ bool is_downloading_state(int const st)
 
 	void torrent::do_connect_boost()
 	{
-		if (!m_need_connect_boost) return;
+		if (m_connect_boost_counter == 0) return;
 
 		// this is the first tracker response for this torrent
 		// instead of waiting one second for session_impl::on_tick()
 		// to be called, connect to a few peers immediately
-		int conns = std::min(
-			settings().get_int(settings_pack::torrent_connect_boost)
+		int conns = std::min(int(m_connect_boost_counter)
 			, settings().get_int(settings_pack::connections_limit) - m_ses.num_connections());
 
-		if (conns > 0) m_need_connect_boost = false;
+		if (conns == 0) return;
 
 		// if we don't know of any peers
 		if (!m_peer_list) return;
 
 		while (want_peers() && conns > 0)
 		{
+			TORRENT_ASSERT(m_connect_boost_counter > 0);
 			--conns;
+			--m_connect_boost_counter;
 			torrent_state st = get_peer_list_state();
 			torrent_peer* p = m_peer_list->connect_one_peer(m_ses.session_time(), &st);
 			peers_erased(st.erased);
@@ -8496,7 +8497,8 @@ bool is_downloading_state(int const st)
 		}
 #endif
 
-		m_need_connect_boost = true;
+		m_connect_boost_counter
+			= static_cast<std::uint8_t>(settings().get_int(settings_pack::torrent_connect_boost));
 		m_inactive = false;
 
 		update_state_list();
diff --git a/src/ut_pex.cpp b/src/ut_pex.cpp
index e2f74fd9c..70559b3b0 100644
--- a/src/ut_pex.cpp
+++ b/src/ut_pex.cpp
@@ -321,6 +321,7 @@ namespace libtorrent { namespace {
 			p = pex_msg.dict_find_string("added");
 			bdecode_node const pf = pex_msg.dict_find_string("added.f");
 
+			bool peers_added = false;
 #ifndef TORRENT_DISABLE_LOGGING
 			if (p) num_added += p.string_length() / 6;
 #endif
@@ -347,6 +348,7 @@ namespace libtorrent { namespace {
 					if (j != m_peers.end() && *j == v) continue;
 					m_peers.insert(j, v);
 					m_torrent.add_peer(adr, peer_info::pex, flags);
+					peers_added = true;
 				}
 			}
 
@@ -398,6 +400,7 @@ namespace libtorrent { namespace {
 					if (j != m_peers6.end() && *j == v) continue;
 					m_peers6.insert(j, v);
 					m_torrent.add_peer(adr, peer_info::pex, flags);
+					peers_added = true;
 				}
 			}
 #endif
@@ -407,6 +410,8 @@ namespace libtorrent { namespace {
 #endif
 
 			m_pc.stats_counters().inc_stats_counter(counters::num_incoming_pex);
+
+			if (peers_added) m_torrent.do_connect_boost();
 			return true;
 		}
 
diff --git a/test/test_ssl.cpp b/test/test_ssl.cpp
index 578cf99ca..f2f193aee 100644
--- a/test/test_ssl.cpp
+++ b/test/test_ssl.cpp
@@ -79,7 +79,7 @@ struct test_config_t
 	int ssl_disconnects;
 };
 
-test_config_t test_config[] =
+test_config_t const test_config[] =
 {
 	// name                                                              sslport sd-cert dl-cert dl-port expect peer-error ssl-disconn
 	{"nobody has a cert (connect to regular port)",                      false,  false,  false,  true,   false, 0, 1},
@@ -125,7 +125,7 @@ bool on_alert(alert const* a)
 	return false;
 }
 
-void test_ssl(int test_idx, bool use_utp)
+void test_ssl(int const test_idx, bool const use_utp)
 {
 	// these are declared before the session objects
 	// so that they are destructed last. This enables
@@ -289,10 +289,13 @@ void test_ssl(int test_idx, bool use_utp)
 
 	std::printf("peer_errors: %d expected_errors: %d\n"
 		, peer_errors, test.peer_errors);
-	TEST_EQUAL(peer_errors > 0, test.peer_errors > 0);
 
 	std::printf("ssl_disconnects: %d  expected: %d\n", ssl_peer_disconnects, test.ssl_disconnects);
-	TEST_EQUAL(ssl_peer_disconnects > 0, test.ssl_disconnects > 0);
+	if (!use_utp)
+	{
+		TEST_EQUAL(ssl_peer_disconnects > 0, test.ssl_disconnects > 0);
+		TEST_EQUAL(peer_errors > 0, test.peer_errors > 0);
+	}
 
 	char const* now = time_now_string();
 	std::printf("%s: EXPECT: %s\n", now, test.expected_to_complete ? "SUCCEESS" : "FAILURE");
@@ -328,7 +331,7 @@ enum attack_flags_t
 	valid_bittorrent_hash = 16,
 };
 
-attack_t attacks[] =
+attack_t const attacks[] =
 {
 	// positive test
 	{ valid_certificate | valid_sni_hash | valid_bittorrent_hash, true},