fix(EnsureAvailableMemory/macOS): warn based on memory pressure rather than available RAM

Signed-off-by: Octol1ttle <l1ttleofficial@outlook.com>

launcher/HardwareInfo.cpp

@@ -141,7 +141,6 @@ uint64_t HardwareInfo::availableRamMiB()
 }
 
 #elif defined(Q_OS_MACOS)
-#include "mach/mach.h"
 #include "sys/sysctl.h"
 
 QString HardwareInfo::cpuInfo()
@@ -171,18 +170,32 @@ uint64_t HardwareInfo::totalRamMiB()
 
 uint64_t HardwareInfo::availableRamMiB()
 {
-    mach_port_t host_port = mach_host_self();
-    mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
+    return 0;
+}
 
-    vm_statistics64_data_t vm_stats;
-
-    if (host_statistics64(host_port, HOST_VM_INFO64, reinterpret_cast<host_info64_t>(&vm_stats), &count) == KERN_SUCCESS) {
-        // transforming bytes -> mib
-        return (vm_stats.free_count + vm_stats.inactive_count) * vm_page_size / 1024 / 1024;
+MacOSHardwareInfo::MemoryPressureLevel MacOSHardwareInfo::memoryPressureLevel()
+{
+    uint32_t level;
+    size_t levelSize = sizeof level;
+    if (sysctlbyname("kern.memorystatus_vm_pressure_level", &level, &levelSize, nullptr, 0) == 0) {
+        return static_cast<MemoryPressureLevel>(level);
     }
 
-    qWarning() << "Could not get available RAM: host_statistics64";
-    return 0;
+    qWarning() << "Could not get memory pressure level: sysctlbyname";
+    return MemoryPressureLevel::Normal;
+}
+
+QString MacOSHardwareInfo::memoryPressureLevelName()
+{
+    // The names are internal, users refer to levels by their graph colors in Activity Monitor
+    switch (memoryPressureLevel()) {
+        case MemoryPressureLevel::Normal:
+            return "Green";
+        case MemoryPressureLevel::Warning:
+            return "Yellow";
+        case MemoryPressureLevel::Critical:
+            return "Red";
+    }
 }
 
 #elif defined(Q_OS_LINUX)

launcher/HardwareInfo.h

@@ -27,3 +27,16 @@ uint64_t totalRamMiB();
 uint64_t availableRamMiB();
 QStringList gpuInfo();
 }  // namespace HardwareInfo
+
+#ifdef Q_OS_MACOS
+namespace MacOSHardwareInfo {
+enum class MemoryPressureLevel : uint8_t {
+    Normal = 1,
+    Warning = 2,
+    Critical = 4,
+};
+
+MemoryPressureLevel memoryPressureLevel();
+QString memoryPressureLevelName();
+}  // namespace MacOSHardwareInfo
+#endif

launcher/minecraft/launch/EnsureAvailableMemory.cpp

@@ -25,6 +25,47 @@ EnsureAvailableMemory::EnsureAvailableMemory(LaunchTask* parent, MinecraftInstan
 
 void EnsureAvailableMemory::executeTask()
 {
+#ifdef Q_OS_MACOS
+    QString text;
+    switch (MacOSHardwareInfo::memoryPressureLevel()) {
+        case MacOSHardwareInfo::MemoryPressureLevel::Normal:
+            emitSucceeded();
+            return;
+        case MacOSHardwareInfo::MemoryPressureLevel::Warning:
+            text =
+                tr("The system is under increased memory pressure. This may cause lag or slowdowns.\n"
+                   "If possible, close other applications before continuing.\n\n"
+                   "Launch anyway?");
+            break;
+        case MacOSHardwareInfo::MemoryPressureLevel::Critical:
+            text =
+                tr("Your system is under critical memory pressure. This may lead to severe slowdowns or crashes.\n"
+                   "It is highly recommended to close other applications or restart your system.\n\n"
+                   "Launch anyway?");
+            break;
+    }
+
+    bool shouldAbort = false;
+
+    if (m_instance->settings()->get("LowMemWarning").toBool()) {
+        auto* dialog = CustomMessageBox::selectable(nullptr, tr("High memory pressure"), text, QMessageBox::Icon::Warning,
+                                                    QMessageBox::StandardButton::Yes | QMessageBox::StandardButton::No,
+                                                    QMessageBox::StandardButton::No);
+
+        shouldAbort = dialog->exec() == QMessageBox::No;
+        dialog->deleteLater();
+    }
+
+    const auto message = tr("The system is under high memory pressure");
+    if (shouldAbort) {
+        emit logLine(message, MessageLevel::Fatal);
+        emitFailed(message);
+        return;
+    }
+
+    emit logLine(message, MessageLevel::Warning);
+    emitSucceeded();
+#else
     const uint64_t available = HardwareInfo::availableRamMiB();
     if (available == 0) {
         // could not read
@@ -66,4 +107,5 @@ void EnsureAvailableMemory::executeTask()
     }
 
     emitSucceeded();
+#endif
 }

launcher/minecraft/launch/PrintInstanceInfo.cpp

@@ -68,7 +68,12 @@ void PrintInstanceInfo::executeTask()
     ::runPciconf(log);
 #else
     log << "CPU: " + HardwareInfo::cpuInfo();
+#ifdef Q_OS_MACOS
+    log << "Memory pressure level: " + MacOSHardwareInfo::memoryPressureLevelName();
+#else
     log << QString("RAM: %1 MiB (available: %2 MiB)").arg(HardwareInfo::totalRamMiB()).arg(HardwareInfo::availableRamMiB());
+#endif
+
 #endif
     log.append(HardwareInfo::gpuInfo());
     log << "";