diff --git a/include/bitcoin/network/messages/block.hpp b/include/bitcoin/network/messages/block.hpp
index 1c5e4626c..eee6d00f3 100644
--- a/include/bitcoin/network/messages/block.hpp
+++ b/include/bitcoin/network/messages/block.hpp
@@ -38,6 +38,8 @@ struct BCT_API block
     static const uint32_t version_minimum;
     static const uint32_t version_maximum;
 
+    static cptr deserialize(auto& memory, uint32_t version,
+        const system::data_chunk& data, bool witness=true) NOEXCEPT;
     static cptr deserialize(uint32_t version, const system::data_chunk& data,
         bool witness=true) NOEXCEPT;
     static block deserialize(uint32_t version, system::reader& source,
@@ -51,7 +53,6 @@ struct BCT_API block
     size_t size(uint32_t version, bool witness) const NOEXCEPT;
 
     system::chain::block::cptr block_ptr;
-    mutable size_t cached_size{};
 };
 
 } // namespace messages
diff --git a/include/bitcoin/network/net/channel.hpp b/include/bitcoin/network/net/channel.hpp
index 5f4244d2f..82a688d4d 100644
--- a/include/bitcoin/network/net/channel.hpp
+++ b/include/bitcoin/network/net/channel.hpp
@@ -28,6 +28,7 @@
 #include <bitcoin/network/messages/messages.hpp>
 #include <bitcoin/network/net/broadcaster.hpp>
 #include <bitcoin/network/net/deadline.hpp>
+#include <bitcoin/network/net/memory.hpp>
 #include <bitcoin/network/net/proxy.hpp>
 #include <bitcoin/network/settings.hpp>
 
@@ -73,7 +74,7 @@ class BCT_API channel
     }
 
     /// Construct a channel to encapsulated and communicate on the socket.
-    channel(const logger& log, const socket::ptr& socket, 
+    channel(memory& memory, const logger& log, const socket::ptr& socket,
         const settings& settings, uint64_t identifier=zero,
         bool quiet=true) NOEXCEPT;
 
diff --git a/include/bitcoin/network/net/distributor.hpp b/include/bitcoin/network/net/distributor.hpp
index 822746d4c..f7cec7cf9 100644
--- a/include/bitcoin/network/net/distributor.hpp
+++ b/include/bitcoin/network/net/distributor.hpp
@@ -25,6 +25,7 @@
 #include <bitcoin/network/async/async.hpp>
 #include <bitcoin/network/define.hpp>
 #include <bitcoin/network/messages/messages.hpp>
+#include <bitcoin/network/net/memory.hpp>
 
 namespace libbitcoin {
 namespace network {
@@ -84,7 +85,7 @@ class BCT_API distributor
     DEFINE_SUBSCRIBER(version_acknowledge);
 
     /// Create an instance of this class.
-    distributor(asio::strand& strand) NOEXCEPT;
+    distributor(memory& memory, asio::strand& strand) NOEXCEPT;
 
     /// If stopped, handler is invoked with error::subscriber_stopped.
     /// If key exists, handler is invoked with error::subscriber_exists.
@@ -115,9 +116,9 @@ class BCT_API distributor
         if (!is_zero(subscriber.size()))
         {
             // Subscribers are notified only with stop code or error::success.
-            const auto message = messages::deserialize<Message>(data, version);
-            if (!message) return error::invalid_message;
-            subscriber.notify(error::success, message);
+            const auto ptr = messages::deserialize<Message>(data, version);
+            if (!ptr) return error::invalid_message;
+            subscriber.notify(error::success, ptr);
         }
 
         return error::success;
@@ -191,8 +192,15 @@ class BCT_API distributor
     DECLARE_SUBSCRIBER(transaction);
     DECLARE_SUBSCRIBER(version);
     DECLARE_SUBSCRIBER(version_acknowledge);
+
+    memory& memory_;
 };
 
+template <>
+code distributor::do_notify<messages::block>(
+    distributor::block_subscriber& subscriber, uint32_t version,
+    const system::data_chunk& data) NOEXCEPT;
+
 #undef SUBSCRIBER
 #undef SUBSCRIBER_TYPE
 #undef DEFINE_SUBSCRIBER
diff --git a/include/bitcoin/network/net/memory.hpp b/include/bitcoin/network/net/memory.hpp
index 11099dbec..87ec26176 100644
--- a/include/bitcoin/network/net/memory.hpp
+++ b/include/bitcoin/network/net/memory.hpp
@@ -38,8 +38,8 @@ class BCT_API memory
     arena* get_arena() NOEXCEPT;
     retainer::ptr get_retainer() NOEXCEPT;
 
-
 private:
+    // These are thread safe.
     arena* arena_;
     std::shared_mutex remap_mutex_{};
 };
diff --git a/include/bitcoin/network/net/proxy.hpp b/include/bitcoin/network/net/proxy.hpp
index 135ade37b..3320e2a1c 100644
--- a/include/bitcoin/network/net/proxy.hpp
+++ b/include/bitcoin/network/net/proxy.hpp
@@ -29,6 +29,7 @@
 #include <bitcoin/network/define.hpp>
 #include <bitcoin/network/messages/messages.hpp>
 #include <bitcoin/network/net/distributor.hpp>
+#include <bitcoin/network/net/memory.hpp>
 #include <bitcoin/network/net/socket.hpp>
 
 namespace libbitcoin {
@@ -122,7 +123,7 @@ class BCT_API proxy
     const config::address& address() const NOEXCEPT;
 
 protected:
-    proxy(const socket::ptr& socket) NOEXCEPT;
+    proxy(memory& memory, const socket::ptr& socket) NOEXCEPT;
 
     /// Property values provided to the proxy.
     virtual size_t minimum_buffer() const NOEXCEPT = 0;
diff --git a/src/messages/block.cpp b/src/messages/block.cpp
index e384fa912..7a6dccb6b 100644
--- a/src/messages/block.cpp
+++ b/src/messages/block.cpp
@@ -43,6 +43,13 @@ typename block::cptr block::deserialize(uint32_t version,
     const system::data_chunk& data, bool witness) NOEXCEPT
 {
     static memory memory{};
+    return deserialize(memory, version, data, witness);
+}
+
+// static
+typename block::cptr block::deserialize(auto& memory, uint32_t version,
+    const system::data_chunk& data, bool witness) NOEXCEPT
+{
     system::istream source{ data };
     system::byte_reader reader{ source, memory.get_arena() };
 
@@ -86,6 +93,7 @@ typename block::cptr block::deserialize(uint32_t version,
         std::advance(start, full);
     }
 
+    // WARNING: retainer does not track objects shared from block (e.g. tx).
     message->block_ptr->set_retainer(memory.get_retainer());
     return message;
 }
@@ -97,10 +105,7 @@ block block::deserialize(uint32_t version, reader& source,
     if (version < version_minimum || version > version_maximum)
         source.invalidate();
 
-    const auto start = source.get_read_position();
-    const auto block_ptr = to_shared<chain::block>(source, witness);
-    const auto size = source.get_read_position() - start;
-    return { block_ptr, size };
+    return { to_shared<chain::block>(source, witness) };
 }
 
 bool block::serialize(uint32_t version,
@@ -116,14 +121,12 @@ void block::serialize(uint32_t BC_DEBUG_ONLY(version), writer& sink,
     bool witness) const NOEXCEPT
 {
     BC_DEBUG_ONLY(const auto bytes = size(version, witness);)
-    ////BC_DEBUG_ONLY(const auto start = sink.get_write_position();)
-    const auto start = sink.get_write_position();
+    BC_DEBUG_ONLY(const auto start = sink.get_write_position();)
 
     if (block_ptr)
         block_ptr->to_data(sink, witness);
 
-    cached_size = sink.get_write_position() - start;
-    BC_ASSERT(sink && cached_size == bytes);
+    BC_ASSERT(sink && (sink.get_write_position() - start) == bytes);
 }
 
 size_t block::size(uint32_t, bool witness) const NOEXCEPT
diff --git a/src/net/channel.cpp b/src/net/channel.cpp
index e5b5440e0..2283c4ece 100644
--- a/src/net/channel.cpp
+++ b/src/net/channel.cpp
@@ -27,6 +27,7 @@
 #include <bitcoin/network/log/log.hpp>
 #include <bitcoin/network/messages/messages.hpp>
 #include <bitcoin/network/net/deadline.hpp>
+#include <bitcoin/network/net/memory.hpp>
 #include <bitcoin/network/net/proxy.hpp>
 #include <bitcoin/network/settings.hpp>
 
@@ -53,9 +54,9 @@ inline deadline::ptr expiration(const logger& log, asio::strand& strand,
     return timeout(log, strand, pseudo_random::duration(span));
 }
 
-channel::channel(const logger& log, const socket::ptr& socket,
+channel::channel(memory& memory, const logger& log, const socket::ptr& socket,
     const settings& settings, uint64_t identifier, bool quiet) NOEXCEPT
-  : proxy(socket),
+  : proxy(memory, socket),
     quiet_(quiet),
     settings_(settings),
     identifier_(identifier),
diff --git a/src/net/distributor.cpp b/src/net/distributor.cpp
index 4a86b708e..8b38fd9a3 100644
--- a/src/net/distributor.cpp
+++ b/src/net/distributor.cpp
@@ -21,6 +21,7 @@
 #include <bitcoin/system.hpp>
 #include <bitcoin/network/async/async.hpp>
 #include <bitcoin/network/messages/messages.hpp>
+#include <bitcoin/network/net/memory.hpp>
 
 namespace libbitcoin {
 namespace network {
@@ -33,7 +34,7 @@ using namespace system;
 #define CASE_NOTIFY(name) case messages::identifier::name: \
     return do_notify<messages::name>(SUBSCRIBER(name), version, data)
 
-distributor::distributor(asio::strand& strand) NOEXCEPT
+distributor::distributor(memory& memory, asio::strand& strand) NOEXCEPT
   : MAKE_SUBSCRIBER(address),
     MAKE_SUBSCRIBER(alert),
     MAKE_SUBSCRIBER(block),
@@ -66,7 +67,8 @@ distributor::distributor(asio::strand& strand) NOEXCEPT
     MAKE_SUBSCRIBER(send_headers),
     MAKE_SUBSCRIBER(transaction),
     MAKE_SUBSCRIBER(version),
-    MAKE_SUBSCRIBER(version_acknowledge)
+    MAKE_SUBSCRIBER(version_acknowledge),
+    memory_(memory)
 {
 }
 
@@ -152,6 +154,21 @@ void distributor::stop(const code& ec) NOEXCEPT
     STOP_SUBSCRIBER(version_acknowledge);
 }
 
+template <>
+code distributor::do_notify<messages::block>(
+    distributor::block_subscriber& subscriber, uint32_t version,
+    const system::data_chunk& data) NOEXCEPT
+{
+    if (!is_zero(subscriber.size()))
+    {
+        const auto ptr = messages::block::deserialize(memory_, version, data);
+        if (!ptr) return error::invalid_message;
+        subscriber.notify(error::success, ptr);
+    }
+
+    return error::success;
+}
+
 #undef SUBSCRIBER
 #undef MAKE_SUBSCRIBER
 #undef CASE_NOTIFY
diff --git a/src/net/proxy.cpp b/src/net/proxy.cpp
index 59f40f95d..f25734d6d 100644
--- a/src/net/proxy.cpp
+++ b/src/net/proxy.cpp
@@ -25,6 +25,7 @@
 #include <bitcoin/network/async/async.hpp>
 #include <bitcoin/network/define.hpp>
 #include <bitcoin/network/log/log.hpp>
+#include <bitcoin/network/net/memory.hpp>
 
 namespace libbitcoin {
 namespace network {
@@ -47,10 +48,10 @@ static constexpr uint32_t https_magic = 0x02010316;
 // This is created in a started state and must be stopped, as the subscribers
 // assert if not stopped. Subscribers may hold protocols even if the service
 // is not started.
-proxy::proxy(const socket::ptr& socket) NOEXCEPT
+proxy::proxy(memory& memory, const socket::ptr& socket) NOEXCEPT
   : socket_(socket),
     stop_subscriber_(socket->strand()),
-    distributor_(socket->strand()),
+    distributor_(memory, socket->strand()),
     reporter(socket->log)
 {
 }
diff --git a/src/sessions/session.cpp b/src/sessions/session.cpp
index ad7ac8d35..98ca02642 100644
--- a/src/sessions/session.cpp
+++ b/src/sessions/session.cpp
@@ -443,9 +443,12 @@ channel::ptr session::create_channel(const socket::ptr& socket,
 {
     BC_ASSERT_MSG(stranded(), "strand");
 
+    // Default message memory resource, override create_channel to replace.
+    static memory memory{};
+
     // Channel id must be created using create_key().
     const auto id = create_key();
-    return std::make_shared<channel>(log, socket, settings(), id, quiet);
+    return std::make_shared<channel>(memory, log, socket, settings(), id, quiet);
 }
 
 // At one object/session/ns, this overflows in ~585 years (and handled).
diff --git a/test/net/channel.cpp b/test/net/channel.cpp
index c55cb51f3..8f8ac58c7 100644
--- a/test/net/channel.cpp
+++ b/test/net/channel.cpp
@@ -49,12 +49,13 @@ class channel_accessor
 
 BOOST_AUTO_TEST_CASE(channel__stopped__default__false)
 {
+    memory memory{};
     const logger log{};
     threadpool pool(1);
     asio::strand strand(pool.service().get_executor());
     const settings set(bc::system::chain::selection::mainnet);
     auto socket_ptr = std::make_shared<network::socket>(log, pool.service());
-    auto channel_ptr = std::make_shared<channel>(log, socket_ptr, set, 42);
+    auto channel_ptr = std::make_shared<channel>(memory, log, socket_ptr, set, 42);
     BOOST_REQUIRE(!channel_ptr->stopped());
 
     // Stop completion is asynchronous.
@@ -70,12 +71,13 @@ inline size_t payload_maximum(const settings& settings)
 
 BOOST_AUTO_TEST_CASE(channel__properties__default__expected)
 {
+    memory memory{};
     const logger log{};
     threadpool pool(1);
     asio::strand strand(pool.service().get_executor());
     const settings set(bc::system::chain::selection::mainnet);
     auto socket_ptr = std::make_shared<network::socket>(log, pool.service());
-    auto channel_ptr = std::make_shared<channel_accessor>(log, socket_ptr, set, 42);
+    auto channel_ptr = std::make_shared<channel_accessor>(memory, log, socket_ptr, set, 42);
 
     BOOST_REQUIRE(!channel_ptr->address());
     BOOST_REQUIRE_NE(channel_ptr->nonce(), 0u);
diff --git a/test/net/distributor.cpp b/test/net/distributor.cpp
index bcfae4d6a..010ec3ea1 100644
--- a/test/net/distributor.cpp
+++ b/test/net/distributor.cpp
@@ -22,9 +22,10 @@ BOOST_AUTO_TEST_SUITE(distributor_tests)
 
 BOOST_AUTO_TEST_CASE(distributor__construct__stop__stops)
 {
+    memory memory{};
     threadpool pool(2);
     asio::strand strand(pool.service().get_executor());
-    distributor instance(strand);
+    distributor instance(memory, strand);
 
     std::promise<bool> promise;
     boost::asio::post(strand, [&]() NOEXCEPT
@@ -40,9 +41,10 @@ BOOST_AUTO_TEST_CASE(distributor__construct__stop__stops)
 
 BOOST_AUTO_TEST_CASE(distributor__subscribe__stop__expected_code)
 {
+    memory memory{};
     threadpool pool(2);
     asio::strand strand(pool.service().get_executor());
-    distributor instance(strand);
+    distributor instance(memory, strand);
     constexpr auto expected_ec = error::invalid_magic;
     auto result = true;
 
@@ -71,9 +73,10 @@ BOOST_AUTO_TEST_CASE(distributor__subscribe__stop__expected_code)
 
 BOOST_AUTO_TEST_CASE(distributor__notify__invalid_message__no_notification)
 {
+    memory memory{};
     threadpool pool(2);
     asio::strand strand(pool.service().get_executor());
-    distributor instance(strand);
+    distributor instance(memory, strand);
     constexpr auto expected_ec = error::invalid_magic;
     auto result = true;
 
@@ -113,9 +116,10 @@ BOOST_AUTO_TEST_CASE(distributor__notify__invalid_message__no_notification)
 
 BOOST_AUTO_TEST_CASE(distributor__notify__valid_message_invalid_version__no_notification)
 {
+    memory memory{};
     threadpool pool(2);
     asio::strand strand(pool.service().get_executor());
-    distributor instance(strand);
+    distributor instance(memory, strand);
     constexpr auto expected_ec = error::invalid_magic;
     auto result = true;
 
@@ -153,9 +157,10 @@ BOOST_AUTO_TEST_CASE(distributor__notify__valid_message_invalid_version__no_noti
 
 BOOST_AUTO_TEST_CASE(distributor__notify__valid_nonced_ping__expected_notification)
 {
+    memory memory{};
     threadpool pool(2);
     asio::strand strand(pool.service().get_executor());
-    distributor instance(strand);
+    distributor instance(memory, strand);
     constexpr uint64_t expected_nonce = 42;
     constexpr auto expected_ec = error::invalid_magic;
     auto result = true;
diff --git a/test/net/proxy.cpp b/test/net/proxy.cpp
index 3e948de95..a02ab06a0 100644
--- a/test/net/proxy.cpp
+++ b/test/net/proxy.cpp
@@ -37,8 +37,8 @@ class mock_proxy
         proxy::subscribe_stop(std::move(handler));
     }
 
-    mock_proxy(socket::ptr socket) NOEXCEPT
-      : proxy(socket)
+    mock_proxy(const socket::ptr& socket) NOEXCEPT
+      : proxy(memory_, socket)
     {
     }
 
@@ -88,6 +88,7 @@ class mock_proxy
     }
 
 private:
+    mutable memory memory_{};
     mutable bool stop_{ false };
     mutable std::promise<code> stopped_;
 };
diff --git a/test/sessions/session.cpp b/test/sessions/session.cpp
index 24b099cdd..8ac7b044d 100644
--- a/test/sessions/session.cpp
+++ b/test/sessions/session.cpp
@@ -579,6 +579,7 @@ BOOST_AUTO_TEST_CASE(session__start__stop__success)
 
 BOOST_AUTO_TEST_CASE(session__start_channel__session_not_started__handlers_service_stopped_channel_service_stopped_not_pent_or_stored)
 {
+    memory memory{};
     const logger log{};
     settings set(selection::mainnet);
     mock_p2p net(set, log);
@@ -586,7 +587,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__session_not_started__handlers_servi
     BOOST_REQUIRE(session->stopped());
 
     const auto socket = std::make_shared<network::socket>(net.log, net.service());
-    const auto channel = std::make_shared<mock_channel>(net.log, socket, session->settings(), 42);
+    const auto channel = std::make_shared<mock_channel>(memory, net.log, socket, session->settings(), 42);
 
     std::promise<code> started_channel;
     std::promise<code> stopped_channel;
@@ -624,6 +625,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__session_not_started__handlers_servi
 
 BOOST_AUTO_TEST_CASE(session__start_channel__channel_not_started__handlers_channel_stopped_channel_channel_stopped_stored_and_not_counted)
 {
+    memory memory{};
     const logger log{};
     settings set(selection::mainnet);
     mock_p2p net(set, log);
@@ -641,7 +643,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__channel_not_started__handlers_chann
     BOOST_REQUIRE_EQUAL(started.get_future().get(), error::success);
 
     const auto socket = std::make_shared<network::socket>(net.log, net.service());
-    const auto channel = std::make_shared<mock_channel>(net.log, socket, session->settings(), 42);
+    const auto channel = std::make_shared<mock_channel>(memory, net.log, socket, session->settings(), 42);
 
     // Stop the channel (started by default).
     std::promise<bool> unstarted_channel;
@@ -701,6 +703,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__channel_not_started__handlers_chann
 
 BOOST_AUTO_TEST_CASE(session__start_channel__all_started__handlers_expected_channel_service_stopped_stored_and_counted)
 {
+    memory memory{};
     const logger log{};
     settings set(selection::mainnet);
     set.host_pool_capacity = 0;
@@ -730,7 +733,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__all_started__handlers_expected_chan
     BOOST_REQUIRE_EQUAL(started.get_future().get(), error::success);
 
     const auto socket = std::make_shared<network::socket>(net.log, net.service());
-    const auto channel = std::make_shared<mock_channel>(net.log, socket, session->settings(), 42);
+    const auto channel = std::make_shared<mock_channel>(memory, net.log, socket, session->settings(), 42);
     
     std::promise<code> started_channel;
     std::promise<code> stopped_channel;
@@ -781,6 +784,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__all_started__handlers_expected_chan
 
 BOOST_AUTO_TEST_CASE(session__start_channel__outbound_all_started__handlers_expected_channel_success_stored_and_counted)
 {
+    memory memory{};
     const logger log{};
     settings set(selection::mainnet);
     set.host_pool_capacity = 0;
@@ -811,7 +815,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__outbound_all_started__handlers_expe
     BOOST_REQUIRE_EQUAL(started.get_future().get(), error::success);
 
     const auto socket = std::make_shared<network::socket>(net.log, net.service());
-    const auto channel = std::make_shared<mock_channel_no_read>(net.log, socket, session->settings(), 42);
+    const auto channel = std::make_shared<mock_channel_no_read>(memory, net.log, socket, session->settings(), 42);
     
     std::promise<code> started_channel;
     std::promise<code> stopped_channel;
@@ -864,6 +868,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__outbound_all_started__handlers_expe
 
 BOOST_AUTO_TEST_CASE(session__start_channel__inbound_all_started__handlers_expected_channel_success_not_stored_and_counted)
 {
+    memory memory{};
     const logger log{};
     settings set(selection::mainnet);
     set.host_pool_capacity = 0;
@@ -894,7 +899,7 @@ BOOST_AUTO_TEST_CASE(session__start_channel__inbound_all_started__handlers_expec
     BOOST_REQUIRE_EQUAL(started.get_future().get(), error::success);
 
     const auto socket = std::make_shared<network::socket>(net.log, net.service());
-    const auto channel = std::make_shared<mock_channel_no_read>(net.log, socket, session->settings(), 42);
+    const auto channel = std::make_shared<mock_channel_no_read>(memory, net.log, socket, session->settings(), 42);
     
     std::promise<code> started_channel;
     std::promise<code> stopped_channel;