Allow to use POSIX-compliant disk IO type

This patch allows user to switch disk IO type between memory mapped files based type (default in libtorrent 2, and seems causing memory issues) and POSIX-compliant type which is more conservative on memory usage.

Co-authored-by: Chocobo1 <Chocobo1@users.noreply.github.com>
Co-authored-by: Vladimir Golovnev (Glassez) <glassez@yandex.ru>

PR #16895.

src/base/bittorrent/customstorage.cpp

@@ -34,6 +34,8 @@
 #include "common.h"
 
 #ifdef QBT_USES_LIBTORRENT2
+#include <libtorrent/mmap_disk_io.hpp>
+#include <libtorrent/posix_disk_io.hpp>
 #include <libtorrent/session.hpp>
 
 std::unique_ptr<lt::disk_interface> customDiskIOConstructor(
@@ -42,6 +44,18 @@ std::unique_ptr<lt::disk_interface> customDiskIOConstructor(
     return std::make_unique<CustomDiskIOThread>(lt::default_disk_io_constructor(ioContext, settings, counters));
 }
 
+std::unique_ptr<lt::disk_interface> customPosixDiskIOConstructor(
+        lt::io_context &ioContext, const lt::settings_interface &settings, lt::counters &counters)
+{
+    return std::make_unique<CustomDiskIOThread>(lt::posix_disk_io_constructor(ioContext, settings, counters));
+}
+
+std::unique_ptr<lt::disk_interface> customMMapDiskIOConstructor(
+        lt::io_context &ioContext, const lt::settings_interface &settings, lt::counters &counters)
+{
+    return std::make_unique<CustomDiskIOThread>(lt::mmap_disk_io_constructor(ioContext, settings, counters));
+}
+
 CustomDiskIOThread::CustomDiskIOThread(std::unique_ptr<libtorrent::disk_interface> nativeDiskIOThread)
     : m_nativeDiskIO {std::move(nativeDiskIOThread)}
 {

src/base/bittorrent/customstorage.h

@@ -50,6 +50,10 @@
 #ifdef QBT_USES_LIBTORRENT2
 std::unique_ptr<lt::disk_interface> customDiskIOConstructor(
         lt::io_context &ioContext, lt::settings_interface const &settings, lt::counters &counters);
+std::unique_ptr<lt::disk_interface> customPosixDiskIOConstructor(
+        lt::io_context &ioContext, lt::settings_interface const &settings, lt::counters &counters);
+std::unique_ptr<lt::disk_interface> customMMapDiskIOConstructor(
+        lt::io_context &ioContext, lt::settings_interface const &settings, lt::counters &counters);
 
 class CustomDiskIOThread final : public lt::disk_interface
 {

src/base/bittorrent/session.cpp

@@ -381,6 +381,7 @@ Session::Session(QObject *parent)
     , m_diskCacheSize(BITTORRENT_SESSION_KEY(u"DiskCacheSize"_qs), -1)
     , m_diskCacheTTL(BITTORRENT_SESSION_KEY(u"DiskCacheTTL"_qs), 60)
     , m_diskQueueSize(BITTORRENT_SESSION_KEY(u"DiskQueueSize"_qs), (1024 * 1024))
+    , m_diskIOType(BITTORRENT_SESSION_KEY(u"DiskIOType"_qs), DiskIOType::Default)
     , m_useOSCache(BITTORRENT_SESSION_KEY(u"UseOSCache"_qs), true)
 #ifdef Q_OS_WIN
     , m_coalesceReadWriteEnabled(BITTORRENT_SESSION_KEY(u"CoalesceReadWrite"_qs), true)
@@ -1149,7 +1150,18 @@ void Session::initializeNativeSession()
     loadLTSettings(pack);
     lt::session_params sessionParams {pack, {}};
 #ifdef QBT_USES_LIBTORRENT2
+    switch (diskIOType())
+    {
+    case DiskIOType::Posix:
+        sessionParams.disk_io_constructor = customPosixDiskIOConstructor;
+        break;
+    case DiskIOType::MMap:
+        sessionParams.disk_io_constructor = customMMapDiskIOConstructor;
+        break;
+    default:
         sessionParams.disk_io_constructor = customDiskIOConstructor;
+        break;
+    }
 #endif
     m_nativeSession = new lt::session {sessionParams};
 
@@ -3363,6 +3375,19 @@ void Session::setPeerTurnoverInterval(const int val)
     configureDeferred();
 }
 
+DiskIOType Session::diskIOType() const
+{
+    return m_diskIOType;
+}
+
+void Session::setDiskIOType(const DiskIOType type)
+{
+    if (type != m_diskIOType)
+    {
+        m_diskIOType = type;
+    }
+}
+
 int Session::requestQueueSize() const
 {
     return m_requestQueueSize;

src/base/bittorrent/session.h

@@ -122,6 +122,14 @@ namespace BitTorrent
         };
         Q_ENUM_NS(ChokingAlgorithm)
 
+        enum class DiskIOType : int
+        {
+            Default = 0,
+            MMap = 1,
+            Posix = 2
+        };
+        Q_ENUM_NS(DiskIOType)
+
         enum class MixedModeAlgorithm : int
         {
             TCP = 0,
@@ -368,6 +376,8 @@ namespace BitTorrent
         void setDiskCacheTTL(int ttl);
         qint64 diskQueueSize() const;
         void setDiskQueueSize(qint64 size);
+        DiskIOType diskIOType() const;
+        void setDiskIOType(DiskIOType type);
         bool useOSCache() const;
         void setUseOSCache(bool use);
         bool isCoalesceReadWriteEnabled() const;
@@ -689,6 +699,7 @@ namespace BitTorrent
         CachedSettingValue<int> m_diskCacheSize;
         CachedSettingValue<int> m_diskCacheTTL;
         CachedSettingValue<qint64> m_diskQueueSize;
+        CachedSettingValue<DiskIOType> m_diskIOType;
         CachedSettingValue<bool> m_useOSCache;
         CachedSettingValue<bool> m_coalesceReadWriteEnabled;
         CachedSettingValue<bool> m_usePieceExtentAffinity;

src/gui/advancedsettings.cpp

@@ -108,6 +108,9 @@ namespace
         DISK_CACHE_TTL,
 #endif
         DISK_QUEUE_SIZE,
+#ifdef QBT_USES_LIBTORRENT2
+        DISK_IO_TYPE,
+#endif
         OS_CACHE,
 #ifndef QBT_USES_LIBTORRENT2
         COALESCE_RW,
@@ -219,6 +222,9 @@ void AdvancedSettings::saveAdvancedSettings()
 #endif
     // Disk queue size
     session->setDiskQueueSize(m_spinBoxDiskQueueSize.value() * 1024);
+#ifdef QBT_USES_LIBTORRENT2
+    session->setDiskIOType(m_comboBoxDiskIOType.currentData().value<BitTorrent::DiskIOType>());
+#endif
     // Enable OS cache
     session->setUseOSCache(m_checkBoxOsCache.isChecked());
 #ifndef QBT_USES_LIBTORRENT2
@@ -521,6 +527,15 @@ void AdvancedSettings::loadAdvancedSettings()
     m_spinBoxDiskQueueSize.setSuffix(tr(" KiB"));
     addRow(DISK_QUEUE_SIZE, (tr("Disk queue size") + u' ' + makeLink(u"https://www.libtorrent.org/reference-Settings.html#max_queued_disk_bytes", u"(?)"))
             , &m_spinBoxDiskQueueSize);
+#ifdef QBT_USES_LIBTORRENT2
+    // Disk IO type
+    m_comboBoxDiskIOType.addItem(tr("Default"), QVariant::fromValue(BitTorrent::DiskIOType::Default));
+    m_comboBoxDiskIOType.addItem(tr("Memory mapped files"), QVariant::fromValue(BitTorrent::DiskIOType::MMap));
+    m_comboBoxDiskIOType.addItem(tr("POSIX-compliant"), QVariant::fromValue(BitTorrent::DiskIOType::Posix));
+    m_comboBoxDiskIOType.setCurrentIndex(m_comboBoxDiskIOType.findData(QVariant::fromValue(session->diskIOType())));
+    addRow(DISK_IO_TYPE, tr("Disk IO type (requires restart)") + u' ' + makeLink(u"https://www.libtorrent.org/single-page-ref.html#default-disk-io-constructor", u"(?)")
+           , &m_comboBoxDiskIOType);
+#endif
     // Enable OS cache
     m_checkBoxOsCache.setChecked(session->useOSCache());
     addRow(OS_CACHE, (tr("Enable OS cache") + u' ' + makeLink(u"https://www.libtorrent.org/reference-Settings.html#disk_io_write_mode", u"(?)"))

src/gui/advancedsettings.h

@@ -76,6 +76,7 @@ private:
     QSpinBox m_spinBoxCache, m_spinBoxCacheTTL;
     QCheckBox m_checkBoxCoalesceRW;
 #else
+    QComboBox m_comboBoxDiskIOType;
     QSpinBox m_spinBoxHashingThreads;
 #endif
 

src/webui/api/appcontroller.cpp

@@ -315,6 +315,8 @@ void AppController::preferencesAction()
     data[u"disk_cache_ttl"_qs] = session->diskCacheTTL();
     // Disk queue size
     data[u"disk_queue_size"_qs] = session->diskQueueSize();
+    // Disk IO Type
+    data[u"disk_io_type"_qs] = static_cast<int>(session->diskIOType());
     // Enable OS cache
     data[u"enable_os_cache"_qs] = session->useOSCache();
     // Coalesce reads & writes
@@ -799,6 +801,9 @@ void AppController::setPreferencesAction()
     // Disk queue size
     if (hasKey(u"disk_queue_size"_qs))
         session->setDiskQueueSize(it.value().toLongLong());
+    // Disk IO Type
+    if (hasKey(u"disk_io_type"_qs))
+        session->setDiskIOType(static_cast<BitTorrent::DiskIOType>(it.value().toInt()));
     // Enable OS cache
     if (hasKey(u"enable_os_cache"_qs))
         session->setUseOSCache(it.value().toBool());

src/webui/www/private/views/preferences.html

@@ -1038,6 +1038,18 @@
                     <input type="text" id="diskQueueSize" style="width: 15em;">&nbsp;&nbsp;QBT_TR(KiB)QBT_TR[CONTEXT=OptionsDialog]
                 </td>
             </tr>
+            <tr>
+                <td>
+                    <label for="diskIOType">QBT_TR(Disk IO type (libtorrent >= 2.0; requires restart):)QBT_TR[CONTEXT=OptionsDialog]&nbsp;<a href="https://www.libtorrent.org/single-page-ref.html#default-disk-io-constructor" target="_blank">(?)</a></label>
+                </td>
+                <td>
+                    <select id="diskIOType" style="width: 15em;">
+                        <option value="0">QBT_TR(Default)QBT_TR[CONTEXT=OptionsDialog]</option>
+                        <option value="1">QBT_TR(Memory mapped files)QBT_TR[CONTEXT=OptionsDialog]</option>
+                        <option value="2">QBT_TR(POSIX-compliant)QBT_TR[CONTEXT=OptionsDialog]</option>
+                    </select>
+                </td>
+            </tr>
             <tr>
                 <td>
                     <label for="enableOSCache">QBT_TR(Enable OS cache:)QBT_TR[CONTEXT=OptionsDialog]&nbsp;<a href="https://www.libtorrent.org/reference-Settings.html#disk_io_write_mode" target="_blank">(?)</a></label>
@@ -1970,6 +1982,7 @@
                         $('diskCache').setProperty('value', pref.disk_cache);
                         $('diskCacheExpiryInterval').setProperty('value', pref.disk_cache_ttl);
                         $('diskQueueSize').setProperty('value', (pref.disk_queue_size / 1024));
+                        $('diskIOType').setProperty('value', pref.disk_io_type);
                         $('enableOSCache').setProperty('checked', pref.enable_os_cache);
                         $('coalesceReadsAndWrites').setProperty('checked', pref.enable_coalesce_read_write);
                         $('pieceExtentAffinity').setProperty('checked', pref.enable_piece_extent_affinity);
@@ -2371,6 +2384,7 @@
             settings.set('disk_cache', $('diskCache').getProperty('value'));
             settings.set('disk_cache_ttl', $('diskCacheExpiryInterval').getProperty('value'));
             settings.set('disk_queue_size', ($('diskQueueSize').getProperty('value') * 1024));
+            settings.set('disk_io_type', $('diskIOType').getProperty('value'));
             settings.set('enable_os_cache', $('enableOSCache').getProperty('checked'));
             settings.set('enable_coalesce_read_write', $('coalesceReadsAndWrites').getProperty('checked'));
             settings.set('enable_piece_extent_affinity', $('pieceExtentAffinity').getProperty('checked'));