pread-disk-io

CMakeLists.txt

@@ -166,6 +166,8 @@ set(libtorrent_aux_include_files
 	disable_warnings_pop.hpp
 	disable_warnings_push.hpp
 	disk_buffer_pool.hpp
+	disk_cache.hpp
+	visit_block_iovecs.hpp
 	disk_completed_queue.hpp
 	mmap_disk_job.hpp
 	disk_job.hpp
@@ -226,6 +228,7 @@ set(libtorrent_aux_include_files
 	portmap.hpp
 	posix_part_file.hpp
 	posix_storage.hpp
+	pread_disk_job.hpp
 	proxy_base.hpp
 	proxy_settings.hpp
 	puff.hpp
@@ -327,6 +330,7 @@ set(sources
 	disabled_disk_io.cpp
 	disk_buffer_holder.cpp
 	disk_buffer_pool.cpp
+	disk_cache.cpp
 	disk_completed_queue.cpp
 	disk_io_thread_pool.cpp
 	disk_job_fence.cpp
@@ -384,6 +388,8 @@ set(sources
 	posix_disk_io.cpp
 	posix_part_file.cpp
 	posix_storage.cpp
+	pread_disk_io.cpp
+	pread_storage.cpp
 	proxy_base.cpp
 	proxy_settings.cpp
 	puff.cpp

ChangeLog

@@ -1,5 +1,6 @@
 2.1.0 not released
 
+	* add a multi-threaded, pread()-based, disk I/O backend (pread_disk_io)
 	* try harder to bind TCP and UDP sockets to the same port
 	* made disk_interface's status_t type a flags type
 	* optimize resume data format to use less space

Jamfile

@@ -796,6 +796,7 @@ SOURCES =
 	directory
 	disk_buffer_holder
 	disk_buffer_pool
+	disk_cache
 	disk_completed_queue
 	disk_io_thread_pool
 	disabled_disk_io
@@ -900,6 +901,8 @@ SOURCES =
 	mmap
 	mmap_disk_io
 	mmap_storage
+	pread_disk_io
+	pread_storage
 	posix_disk_io
 	posix_part_file
 	posix_storage

Makefile

@@ -321,6 +321,7 @@ SOURCES = \
   disabled_disk_io.cpp            \
   disk_buffer_holder.cpp          \
   disk_buffer_pool.cpp            \
+  disk_cache.cpp                  \
   disk_completed_queue.cpp        \
   disk_io_thread_pool.cpp         \
   disk_job_fence.cpp              \
@@ -379,6 +380,8 @@ SOURCES = \
   posix_disk_io.cpp               \
   posix_part_file.cpp             \
   posix_storage.cpp               \
+  pread_disk_io.cpp               \
+  pread_storage.cpp               \
   proxy_base.cpp                  \
   proxy_settings.cpp              \
   puff.cpp                        \
@@ -495,6 +498,7 @@ HEADERS = \
   piece_block.hpp              \
   portmap.hpp                  \
   posix_disk_io.hpp            \
+  pread_disk_io.hpp            \
   read_resume_data.hpp         \
   session.hpp                  \
   session_handle.hpp           \
@@ -560,6 +564,8 @@ HEADERS = \
   aux_/disable_warnings_pop.hpp     \
   aux_/disable_warnings_push.hpp    \
   aux_/disk_buffer_pool.hpp         \
+  aux_/disk_cache.hpp               \
+  aux_/visit_block_iovecs.hpp       \
   aux_/disk_completed_queue.hpp     \
   aux_/disk_io_thread_pool.hpp      \
   aux_/disk_job_fence.hpp           \
@@ -626,6 +632,8 @@ HEADERS = \
   aux_/portmap.hpp                  \
   aux_/posix_part_file.hpp          \
   aux_/posix_storage.hpp            \
+  aux_/pread_disk_job.hpp           \
+  aux_/pread_storage.hpp            \
   aux_/proxy_base.hpp               \
   aux_/proxy_settings.hpp           \
   aux_/puff.hpp                     \

bindings/python/src/session.cpp

@@ -30,6 +30,7 @@
 
 #include <libtorrent/mmap_disk_io.hpp>
 #include <libtorrent/posix_disk_io.hpp>
+#include <libtorrent/pread_disk_io.hpp>
 
 namespace boost
 {
@@ -882,6 +883,8 @@ namespace
 #endif
         if (disk_io == "posix_disk_io_constructor")
             s.disk_io_constructor = &lt::posix_disk_io_constructor;
+        else if (disk_io == "pread_disk_io_constructor")
+            s.disk_io_constructor = &lt::pread_disk_io_constructor;
         else
             s.disk_io_constructor = &lt::default_disk_io_constructor;
     }

examples/client_test.cpp

@@ -56,6 +56,7 @@ see LICENSE file.
 
 #include "libtorrent/mmap_disk_io.hpp"
 #include "libtorrent/posix_disk_io.hpp"
+#include "libtorrent/pread_disk_io.hpp"
 #include "libtorrent/disabled_disk_io.hpp"
 
 #include "torrent_view.hpp"
@@ -1347,7 +1348,7 @@ CLIENT OPTIONS
   -O                    print session stats counters to the log
   -1                    exit on first torrent completing (useful for benchmarks)
   -i <disk-io>          specify which disk I/O back-end to use. One of:
-                        mmap, posix, disabled
+                        mmap, posix, pread, disabled
 )"
 #ifdef TORRENT_UTP_LOG_ENABLE
 R"(
@@ -1561,6 +1562,10 @@ int main(int argc, char* argv[])
 #endif
 				if (arg == "posix"_sv)
 					params.disk_io_constructor = lt::posix_disk_io_constructor;
+#if TORRENT_HAVE_PREAD || defined TORRENT_WINDOWS
+				else if (arg == "pread"_sv)
+					params.disk_io_constructor = lt::pread_disk_io_constructor;
+#endif
 				else if (arg == "disabled"_sv)
 					params.disk_io_constructor = lt::disabled_disk_io_constructor;
 				else

include/libtorrent/aux_/debug_disk_thread.hpp

@@ -24,6 +24,7 @@ see LICENSE file.
 #include <string>
 #include <sstream>
 #include <unordered_map>
+#include <thread>
 
 #include "libtorrent/aux_/disk_job.hpp"
 #include "libtorrent/disk_interface.hpp"
@@ -93,6 +94,10 @@ inline std::string print_job(aux::disk_job const& j)
 				<< " buf-offset:" << j.buffer_offset << " size:" << j.buffer_size << " )";
 		}
 
+		void operator()(job::kick_hasher const& j) const {
+			m_ss << "kick-hasher( piece:" << j.piece << " )";
+		}
+
 	private:
 		std::stringstream& m_ss;
 	};

include/libtorrent/aux_/disk_buffer_pool.hpp

@@ -21,6 +21,7 @@ see LICENSE file.
 #include <mutex>
 #include <functional>
 #include <memory>
+#include <optional>
 
 #include "libtorrent/io_context.hpp"
 #include "libtorrent/span.hpp"
@@ -54,6 +55,8 @@ namespace aux {
 			return m_in_use;
 		}
 
+		std::optional<int> flush_request() const;
+
 		void set_settings(settings_interface const& sett);
 
 	private: