feat: new memory settings

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLGameRepository.java

@@ -296,7 +296,11 @@ public class HMCLGameRepository extends DefaultGameRepository {
                 .setProfileName(Metadata.TITLE)
                 .setGameArguments(StringUtils.tokenize(vs.getMinecraftArgs()))
                 .setJavaArguments(StringUtils.tokenize(vs.getJavaArgs()))
-                .setMaxMemory(vs.getMaxMemory())
+                .setMaxMemory((int)(getAllocatedMemory(
+                        vs.getMaxMemory(),
+                        OperatingSystem.getPhysicalMemoryStatus().orElse(OperatingSystem.PhysicalMemoryStatus.INVALID).getAvailable(),
+                        vs.isAutoMemory()
+                ) / 1024 / 1024))
                 .setMinMemory(vs.getMinMemory())
                 .setMetaspace(Lang.toIntOrNull(vs.getPermSize()))
                 .setWidth(vs.getWidth())
@@ -400,4 +404,8 @@ public class HMCLGameRepository extends DefaultGameRepository {
             return versions.containsKey(id);
         }
     }
+
+    public static long getAllocatedMemory(long minimum, long available, boolean auto) {
+        return auto ? Math.max(minimum, (long) (available * 0.8)) : minimum;
+    }
 }

HMCL/src/main/java/org/jackhuang/hmcl/setting/VersionSetting.java

@@ -237,6 +237,20 @@ public final class VersionSetting implements Cloneable {
         minMemoryProperty.set(minMemory);
     }
 
+    private final BooleanProperty autoMemory = new SimpleBooleanProperty(this, "autoMemory", true);
+
+    public boolean isAutoMemory() {
+        return autoMemory.get();
+    }
+
+    public BooleanProperty autoMemoryProperty() {
+        return autoMemory;
+    }
+
+    public void setAutoMemory(boolean autoMemory) {
+        this.autoMemory.set(autoMemory);
+    }
+
     private final StringProperty preLaunchCommandProperty = new SimpleStringProperty(this, "precalledCommand", "");
 
     public StringProperty preLaunchCommandProperty() {
@@ -558,6 +572,7 @@ public final class VersionSetting implements Cloneable {
         permSizeProperty.addListener(listener);
         maxMemoryProperty.addListener(listener);
         minMemoryProperty.addListener(listener);
+        autoMemory.addListener(listener);
         preLaunchCommandProperty.addListener(listener);
         javaArgsProperty.addListener(listener);
         minecraftArgsProperty.addListener(listener);
@@ -589,6 +604,7 @@ public final class VersionSetting implements Cloneable {
         versionSetting.setPermSize(getPermSize());
         versionSetting.setMaxMemory(getMaxMemory());
         versionSetting.setMinMemory(getMinMemory());
+        versionSetting.setAutoMemory(isAutoMemory());
         versionSetting.setPreLaunchCommand(getPreLaunchCommand());
         versionSetting.setJavaArgs(getJavaArgs());
         versionSetting.setMinecraftArgs(getMinecraftArgs());
@@ -619,6 +635,7 @@ public final class VersionSetting implements Cloneable {
             obj.addProperty("minecraftArgs", src.getMinecraftArgs());
             obj.addProperty("maxMemory", src.getMaxMemory() <= 0 ? OperatingSystem.SUGGESTED_MEMORY : src.getMaxMemory());
             obj.addProperty("minMemory", src.getMinMemory());
+            obj.addProperty("autoMemory", src.isAutoMemory());
             obj.addProperty("permSize", src.getPermSize());
             obj.addProperty("width", src.getWidth());
             obj.addProperty("height", src.getHeight());
@@ -659,6 +676,7 @@ public final class VersionSetting implements Cloneable {
             vs.setMinecraftArgs(Optional.ofNullable(obj.get("minecraftArgs")).map(JsonElement::getAsString).orElse(""));
             vs.setMaxMemory(maxMemoryN);
             vs.setMinMemory(Optional.ofNullable(obj.get("minMemory")).map(JsonElement::getAsInt).orElse(null));
+            vs.setAutoMemory(Optional.ofNullable(obj.get("autoMemory")).map(JsonElement::getAsBoolean).orElse(true));
             vs.setPermSize(Optional.ofNullable(obj.get("permSize")).map(JsonElement::getAsString).orElse(""));
             vs.setWidth(Optional.ofNullable(obj.get("width")).map(JsonElement::getAsJsonPrimitive).map(this::parseJsonPrimitive).orElse(0));
             vs.setHeight(Optional.ofNullable(obj.get("height")).map(JsonElement::getAsJsonPrimitive).map(this::parseJsonPrimitive).orElse(0));

HMCL/src/main/java/org/jackhuang/hmcl/ui/versions/VersionSettingsPage.java

@@ -21,20 +21,17 @@ import com.jfoenix.controls.*;
 import javafx.application.Platform;
 import javafx.beans.InvalidationListener;
 import javafx.beans.binding.Bindings;
-import javafx.beans.property.ReadOnlyObjectProperty;
+import javafx.beans.property.*;
-import javafx.beans.property.ReadOnlyObjectWrapper;
 import javafx.geometry.Insets;
 import javafx.geometry.Pos;
 import javafx.scene.Node;
 import javafx.scene.control.Label;
 import javafx.scene.control.ScrollPane;
 import javafx.scene.image.Image;
-import javafx.scene.layout.BorderPane;
+import javafx.scene.layout.*;
-import javafx.scene.layout.HBox;
-import javafx.scene.layout.StackPane;
-import javafx.scene.layout.VBox;
 import javafx.stage.FileChooser;
 import org.jackhuang.hmcl.game.GameDirectoryType;
+import org.jackhuang.hmcl.game.HMCLGameRepository;
 import org.jackhuang.hmcl.game.NativesDirectoryType;
 import org.jackhuang.hmcl.game.ProcessPriority;
 import org.jackhuang.hmcl.setting.LauncherVisibility;
@@ -47,8 +44,10 @@ import org.jackhuang.hmcl.ui.Controllers;
 import org.jackhuang.hmcl.ui.FXUtils;
 import org.jackhuang.hmcl.ui.construct.*;
 import org.jackhuang.hmcl.ui.decorator.DecoratorPage;
+import org.jackhuang.hmcl.util.Lang;
 import org.jackhuang.hmcl.util.Logging;
 import org.jackhuang.hmcl.util.io.FileUtils;
+import org.jackhuang.hmcl.util.javafx.SafeStringConverter;
 import org.jackhuang.hmcl.util.platform.JavaVersion;
 import org.jackhuang.hmcl.util.platform.OperatingSystem;
 
@@ -58,6 +57,7 @@ import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Arrays;
 import java.util.Optional;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.logging.Level;
 import java.util.stream.Collectors;
 
@@ -76,7 +76,6 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
     private final VBox rootPane;
     private final JFXTextField txtWidth;
     private final JFXTextField txtHeight;
-    private final JFXTextField txtMaxMemory;
     private final JFXTextField txtJVMArgs;
     private final JFXTextField txtGameArgs;
     private final JFXTextField txtMetaspace;
@@ -87,8 +86,8 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
     private final ComponentList componentList;
     private final ComponentList iconPickerItemWrapper;
     private final JFXComboBox<LauncherVisibility> cboLauncherVisibility;
+    private final JFXCheckBox chkAutoAllocate;
     private final JFXCheckBox chkFullscreen;
-    private final Label lblPhysicalMemory;
     private final JFXToggleButton chkNoJVMArgs;
     private final JFXToggleButton chkNoGameCheck;
     private final JFXToggleButton chkNoJVMCheck;
@@ -105,6 +104,10 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
 
     private final InvalidationListener javaListener = any -> initJavaSubtitle();
 
+    private boolean uiVisible = false;
+    private final IntegerProperty maxMemoryProperty = new SimpleIntegerProperty();
+    private final ObjectProperty<OperatingSystem.PhysicalMemoryStatus> memoryStatusProperty = new SimpleObjectProperty<>(OperatingSystem.PhysicalMemoryStatus.INVALID);
+
     public VersionSettingsPage() {
         ScrollPane scrollPane = new ScrollPane();
         scrollPane.setFitToHeight(true);
@@ -163,21 +166,120 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
             gameDirItem.setCustomText(i18n("settings.custom"));
             gameDirItem.setDirectory(true);
 
-            BorderPane maxMemoryPane = new BorderPane();
+            VBox maxMemoryPane = new VBox(8);
             {
-                VBox vbox = new VBox();
+                Label title = new Label(i18n("settings.memory"));
-                maxMemoryPane.setLeft(vbox);
+                VBox.setMargin(title, new Insets(0, 0, 8, 0));
-                Label maxMemoryLabel = new Label(i18n("settings.max_memory"));
-                lblPhysicalMemory = new Label();
-                lblPhysicalMemory.getStyleClass().add("subtitle-label");
-                vbox.getChildren().setAll(maxMemoryLabel, lblPhysicalMemory);
 
-                txtMaxMemory = new JFXTextField();
+                chkAutoAllocate = new JFXCheckBox(i18n("settings.memory.auto_allocate"));
-                maxMemoryPane.setRight(txtMaxMemory);
+                VBox.setMargin(chkAutoAllocate, new Insets(0, 0, 8, 5));
-                BorderPane.setAlignment(txtMaxMemory, Pos.CENTER_RIGHT);
+
-                FXUtils.setValidateWhileTextChanged(txtMaxMemory, true);
+                HBox lowerBoundPane = new HBox();
-                FXUtils.setLimitWidth(txtMaxMemory, 300);
+                lowerBoundPane.setAlignment(Pos.CENTER);
-                txtMaxMemory.setValidators(new NumberValidator(i18n("input.number"), false));
+                VBox.setMargin(lowerBoundPane, new Insets(8, 0, 0, 16));
+                {
+                    Label label = new Label();
+                    label.textProperty().bind(Bindings.createStringBinding(() -> {
+                        if (chkAutoAllocate.isSelected()) {
+                            return i18n("settings.memory.lower_bound");
+                        } else {
+                            return i18n("settings.memory");
+                        }
+                    }, chkAutoAllocate.selectedProperty()));
+
+                    JFXSlider slider = new JFXSlider(0, 1, 0);
+                    HBox.setMargin(slider, new Insets(0, 16, 0, 16));
+                    HBox.setHgrow(slider, Priority.ALWAYS);
+                    slider.setValueFactory(self -> Bindings.createStringBinding(() -> (int)(self.getValue() * 100) + "%", self.valueProperty()));
+                    AtomicBoolean changedByTextField = new AtomicBoolean(false);
+                    FXUtils.onChangeAndOperate(maxMemoryProperty, maxMemory -> {
+                        changedByTextField.set(true);
+                        slider.setValue(maxMemory.intValue() * 1.0 / OperatingSystem.TOTAL_MEMORY);
+                        changedByTextField.set(false);
+                    });
+                    slider.valueProperty().addListener((value, oldVal, newVal) -> {
+                        if (changedByTextField.get()) return;
+                        maxMemoryProperty.set((int)(value.getValue().doubleValue() * OperatingSystem.TOTAL_MEMORY));
+                    });
+
+                    JFXTextField txtMaxMemory = new JFXTextField();
+                    FXUtils.setLimitWidth(txtMaxMemory, 60);
+                    FXUtils.setValidateWhileTextChanged(txtMaxMemory, true);
+                    txtMaxMemory.textProperty().bindBidirectional(maxMemoryProperty, SafeStringConverter.fromInteger());
+                    txtMaxMemory.setValidators(new NumberValidator(i18n("input.number"), false));
+
+                    lowerBoundPane.getChildren().setAll(label, slider, txtMaxMemory, new Label("MB"));
+                }
+
+                BorderPane titlePane = new BorderPane();
+                VBox.setMargin(titlePane, new Insets(0, 0, 0, 16));
+                {
+                    Label left = new Label(i18n("settings.memory.used_per_total"));
+                    left.getStyleClass().add("subtitle-label");
+                    titlePane.setLeft(left);
+
+                    Label right = new Label();
+                    right.textProperty().bind(Bindings.createStringBinding(() -> {
+                        if (chkAutoAllocate.isSelected()) {
+                            return i18n("settings.memory.allocate.auto");
+                        } else {
+                            return i18n("settings.memory.allocate.manual");
+                        }
+                    }, chkAutoAllocate.selectedProperty()));
+                    right.getStyleClass().add("subtitle-label");
+                    titlePane.setRight(right);
+                }
+
+                StackPane progressBarPane = new StackPane();
+                progressBarPane.setAlignment(Pos.CENTER_LEFT);
+                VBox.setMargin(progressBarPane, new Insets(0, 0, 0, 16));
+                {
+                    progressBarPane.setMinHeight(4);
+                    progressBarPane.getStyleClass().add("memory-total");
+
+                    StackPane usedMemory = new StackPane();
+                    usedMemory.getStyleClass().add("memory-used");
+                    usedMemory.maxWidthProperty().bind(Bindings.createDoubleBinding(() ->
+                                    progressBarPane.getWidth() *
+                                            (memoryStatusProperty.get().getUsed() * 1.0 / memoryStatusProperty.get().getTotal()), progressBarPane.widthProperty(),
+                            memoryStatusProperty));
+                    StackPane allocateMemory = new StackPane();
+                    allocateMemory.getStyleClass().add("memory-allocate");
+                    allocateMemory.maxWidthProperty().bind(Bindings.createDoubleBinding(() ->
+                                    progressBarPane.getWidth() *
+                                            Math.min(1.0,
+                                                    (double)(HMCLGameRepository.getAllocatedMemory(maxMemoryProperty.get() * 1024L * 1024L, memoryStatusProperty.get().getAvailable(), chkAutoAllocate.isSelected())
+                                                            + memoryStatusProperty.get().getUsed()) / memoryStatusProperty.get().getTotal()), progressBarPane.widthProperty(),
+                            maxMemoryProperty, memoryStatusProperty, chkAutoAllocate.selectedProperty()));
+
+                    progressBarPane.getChildren().setAll(allocateMemory, usedMemory);
+                }
+
+                BorderPane digitalPane = new BorderPane();
+                VBox.setMargin(digitalPane, new Insets(0, 0, 0, 16));
+                {
+                    Label lblPhysicalMemory = new Label();
+                    lblPhysicalMemory.getStyleClass().add("memory-label");
+                    digitalPane.setLeft(lblPhysicalMemory);
+                    lblPhysicalMemory.textProperty().bind(Bindings.createStringBinding(() -> {
+                        return i18n("settings.memory.used_per_total.format", memoryStatusProperty.get().getUsedGB(), memoryStatusProperty.get().getTotalGB());
+                    }, memoryStatusProperty));
+
+                    Label lblAllocateMemory = new Label();
+                    lblAllocateMemory.textProperty().bind(Bindings.createStringBinding(() -> {
+                        long maxMemory = Lang.parseInt(maxMemoryProperty.get(), 0) * 1024L * 1024L;
+                        return i18n(memoryStatusProperty.get().hasAvailable() && maxMemory > memoryStatusProperty.get().getAvailable()
+                                        ? (chkAutoAllocate.isSelected() ? "settings.memory.allocate.format.auto.exceeded" : "settings.memory.allocate.format.manual.exceeded")
+                                        : (chkAutoAllocate.isSelected() ? "settings.memory.allocate.format.auto" : "settings.memory.allocate.format.manual"),
+                                OperatingSystem.PhysicalMemoryStatus.toGigaBytes(maxMemory),
+                                OperatingSystem.PhysicalMemoryStatus.toGigaBytes(HMCLGameRepository.getAllocatedMemory(maxMemory, memoryStatusProperty.get().getAvailable(), chkAutoAllocate.isSelected())),
+                                OperatingSystem.PhysicalMemoryStatus.toGigaBytes(memoryStatusProperty.get().getAvailable()));
+                    }, memoryStatusProperty, maxMemoryProperty, chkAutoAllocate.selectedProperty()));
+                    lblAllocateMemory.getStyleClass().add("memory-label");
+                    digitalPane.setRight(lblAllocateMemory);
+                }
+
+                maxMemoryPane.getChildren().setAll(title, chkAutoAllocate, lowerBoundPane, titlePane, progressBarPane, digitalPane);
             }
 
             BorderPane launcherVisibilityPane = new BorderPane();
@@ -368,7 +470,7 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
     }
 
     private void initialize() {
-        lblPhysicalMemory.setText(i18n("settings.physical_memory") + ": " + OperatingSystem.TOTAL_MEMORY + "MB");
+        memoryStatusProperty.set(OperatingSystem.getPhysicalMemoryStatus().orElse(OperatingSystem.PhysicalMemoryStatus.INVALID));
 
         Task.supplyAsync(JavaVersion::getJavas).thenAcceptAsync(Schedulers.javafx(), list -> {
             javaItem.loadChildren(list.stream()
@@ -434,7 +536,7 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
         if (lastVersionSetting != null) {
             FXUtils.unbindInt(txtWidth, lastVersionSetting.widthProperty());
             FXUtils.unbindInt(txtHeight, lastVersionSetting.heightProperty());
-            FXUtils.unbindInt(txtMaxMemory, lastVersionSetting.maxMemoryProperty());
+            maxMemoryProperty.unbindBidirectional(lastVersionSetting.maxMemoryProperty());
             FXUtils.unbindString(javaItem.getTxtCustom(), lastVersionSetting.javaDirProperty());
             FXUtils.unbindString(gameDirItem.getTxtCustom(), lastVersionSetting.gameDirProperty());
             FXUtils.unbindString(nativesDirItem.getTxtCustom(), lastVersionSetting.nativesDirProperty());
@@ -444,6 +546,7 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
             FXUtils.unbindString(txtWrapper, lastVersionSetting.wrapperProperty());
             FXUtils.unbindString(txtPrecallingCommand, lastVersionSetting.preLaunchCommandProperty());
             FXUtils.unbindString(txtServerIP, lastVersionSetting.serverIpProperty());
+            FXUtils.unbindBoolean(chkAutoAllocate, lastVersionSetting.autoMemoryProperty());
             FXUtils.unbindBoolean(chkFullscreen, lastVersionSetting.fullscreenProperty());
             FXUtils.unbindBoolean(chkNoGameCheck, lastVersionSetting.notCheckGameProperty());
             FXUtils.unbindBoolean(chkNoJVMCheck, lastVersionSetting.notCheckJVMProperty());
@@ -469,7 +572,7 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
         // bind new data fields
         FXUtils.bindInt(txtWidth, versionSetting.widthProperty());
         FXUtils.bindInt(txtHeight, versionSetting.heightProperty());
-        FXUtils.bindInt(txtMaxMemory, versionSetting.maxMemoryProperty());
+        maxMemoryProperty.bindBidirectional(versionSetting.maxMemoryProperty());
         FXUtils.bindString(javaItem.getTxtCustom(), versionSetting.javaDirProperty());
         FXUtils.bindString(gameDirItem.getTxtCustom(), versionSetting.gameDirProperty());
         FXUtils.bindString(nativesDirItem.getTxtCustom(), versionSetting.nativesDirProperty());
@@ -479,6 +582,7 @@ public final class VersionSettingsPage extends StackPane implements DecoratorPag
         FXUtils.bindString(txtWrapper, versionSetting.wrapperProperty());
         FXUtils.bindString(txtPrecallingCommand, versionSetting.preLaunchCommandProperty());
         FXUtils.bindString(txtServerIP, versionSetting.serverIpProperty());
+        FXUtils.bindBoolean(chkAutoAllocate, versionSetting.autoMemoryProperty());
         FXUtils.bindBoolean(chkFullscreen, versionSetting.fullscreenProperty());
         FXUtils.bindBoolean(chkNoGameCheck, versionSetting.notCheckGameProperty());
         FXUtils.bindBoolean(chkNoJVMCheck, versionSetting.notCheckJVMProperty());

HMCL/src/main/resources/assets/css/root.css

@@ -42,6 +42,22 @@
     -fx-text-fill: rgba(0, 0, 0, 0.5);
 }
 
+.memory-label {
+    -fx-font-size: 14px;
+}
+
+.memory-used {
+    -fx-background-color: -fx-base-darker-color;
+}
+
+.memory-allocate {
+    -fx-background-color: -fx-base-check-color;
+}
+
+.memory-total {
+    -fx-background-color: -fx-base-rippler-color;
+}
+
 .update-label {
     -fx-text-fill: red;
 }
@@ -530,23 +546,12 @@
 *                          							   *
 *******************************************************/
 
-.jfx-slider-style {
+.jfx-slider {
     -jfx-indicator-position: right;
 }
 
-.jfx-slider-style > .thumb {
+.jfx-slider .thumb {
-    -fx-background-color: #03a9f4;
+    -fx-background-color: -fx-base-color;
-}
-
-.jfx-slider-style .track {
-    -fx-background-color: #ff5252;
-    -fx-pref-height: 5px;
-    -fx-pref-width: 5px;
-}
-
-.jfx-slider-style .sliderValue {
-    -fx-stroke: WHITE;
-    -fx-font-size: 10.0;
 }
 
 /*******************************************************************************

HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties

@@ -520,8 +520,17 @@ settings.launcher.proxy.socks=Socks
 settings.launcher.proxy.username=账户
 settings.launcher.theme=主题
 
-settings.min_memory=最小内存（MB）
+settings.memory=游戏内存
-settings.max_memory=最大内存（MB）
+settings.memory.allocate.auto=最低分配 / 实际分配
+settings.memory.allocate.manual=游戏分配
+settings.memory.allocate.format.auto=%1$.1f GB / %2$.1f GB
+settings.memory.allocate.format.auto.exceeded=%1$.1f GB / %2$.1f GB (可用 %3$.1f GB)
+settings.memory.allocate.format.manual=%1$.1f GB
+settings.memory.allocate.format.manual.exceeded=%1$.1f GB (可用 %3$.1f GB)
+settings.memory.auto_allocate=自动分配
+settings.memory.lower_bound=最低分配
+settings.memory.used_per_total=已使用 / 总内存
+settings.memory.used_per_total.format=%1$.1f GB / %2$.1f GB
 settings.physical_memory=物理内存大小
 settings.show_log=查看日志
 settings.tabs.installers=自动安装

HMCLCore/src/main/java/org/jackhuang/hmcl/util/platform/OperatingSystem.java

@@ -17,12 +17,7 @@
  */
 package org.jackhuang.hmcl.util.platform;
 
-import javax.management.JMException;
-import javax.management.MBeanServer;
-import javax.management.ObjectName;
-
 import java.io.File;
-import java.lang.management.ManagementFactory;
 import java.nio.charset.Charset;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -108,7 +103,8 @@ public enum OperatingSystem {
         else
             CURRENT_OS = UNKNOWN;
 
-        TOTAL_MEMORY = getTotalPhysicalMemorySize()
+        TOTAL_MEMORY = getPhysicalMemoryStatus()
+                .map(PhysicalMemoryStatus::getTotal)
                 .map(bytes -> (int) (bytes / 1024 / 1024))
                 .orElse(1024);
 
@@ -133,15 +129,22 @@ public enum OperatingSystem {
         }
     }
 
-    private static Optional<Long> getTotalPhysicalMemorySize() {
+    public static Optional<PhysicalMemoryStatus> getPhysicalMemoryStatus() {
-        MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
+        java.lang.management.OperatingSystemMXBean bean =  java.lang.management.ManagementFactory.getOperatingSystemMXBean();
-        try {
+        if (bean instanceof com.sun.management.OperatingSystemMXBean) {
-            Object attribute = mBeanServer.getAttribute(new ObjectName("java.lang", "type", "OperatingSystem"), "TotalPhysicalMemorySize");
+            com.sun.management.OperatingSystemMXBean sunBean =
-            if (attribute instanceof Long) {
+                    (com.sun.management.OperatingSystemMXBean)
-                return Optional.of((Long) attribute);
+                            java.lang.management.ManagementFactory.getOperatingSystemMXBean();
+
+            if (CURRENT_OS == LINUX) {
+                // On Linux, real amount of memory that is free for using is "available" size of memory,
+                // which also includes size of memory for caching that can be make use of.
+                // But available size of memory cannot be obtained by OperatingSystemMXBean interface.
+                // So we simply disable reporting free physical memory size on Linux.
+                return Optional.of(new PhysicalMemoryStatus(sunBean.getTotalPhysicalMemorySize(), -1));
             }
-        } catch (JMException e) {
+
-            return Optional.empty();
+            return Optional.of(new PhysicalMemoryStatus(sunBean.getTotalPhysicalMemorySize(), sunBean.getFreePhysicalMemorySize()));
         }
         return Optional.empty();
     }
@@ -203,4 +206,48 @@ public enum OperatingSystem {
 
         return true;
     }
+
+    public static class PhysicalMemoryStatus {
+        private final long total;
+        private final long available;
+
+        public PhysicalMemoryStatus(long total, long available) {
+            this.total = total;
+            this.available = available;
+        }
+
+        public long getTotal() {
+            return total;
+        }
+
+        public double getTotalGB() {
+            return toGigaBytes(total);
+        }
+
+        public long getUsed() {
+            return hasAvailable() ? total - available : 0;
+        }
+
+        public double getUsedGB() {
+            return toGigaBytes(getUsed());
+        }
+
+        public long getAvailable() {
+            return available;
+        }
+
+        public double getAvailableGB() {
+            return toGigaBytes(available);
+        }
+
+        public boolean hasAvailable() {
+            return available >= 0;
+        }
+
+        public static double toGigaBytes(long bytes) {
+            return bytes / 1024. / 1024. / 1024.;
+        }
+
+        public static final PhysicalMemoryStatus INVALID = new PhysicalMemoryStatus(0, -1);
+    }
 }