From 95ea6610b18789e5afc3a93a7bccc0a127394517 Mon Sep 17 00:00:00 2001
From: huanghongxun <i@huangyuhui.net>
Date: Fri, 10 Sep 2021 20:58:40 +0800
Subject: [PATCH] feat: use available memory in Linux instead of free memory.

---
 .../hmcl/util/platform/OperatingSystem.java   | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/util/platform/OperatingSystem.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/util/platform/OperatingSystem.java
index 29b2535bc..d4dbc7cc6 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/util/platform/OperatingSystem.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/util/platform/OperatingSystem.java
@@ -18,12 +18,15 @@
 package org.jackhuang.hmcl.util.platform;
 
 import java.io.File;
+import java.io.IOException;
 import java.nio.charset.Charset;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Arrays;
 import java.util.Locale;
 import java.util.Optional;
+import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 /**
@@ -129,7 +132,36 @@ public enum OperatingSystem {
         }
     }
 
+    private static final Pattern MEMINFO_PATTERN = Pattern.compile("^(?<key>.*?):\\s+(?<value>\\d+) kB?$");
+
     public static Optional<PhysicalMemoryStatus> getPhysicalMemoryStatus() {
+        if (CURRENT_OS == LINUX) {
+            try {
+                long free = 0, available = 0, total = 0;
+                for (String line : Files.readAllLines(Paths.get("/proc/meminfo"))) {
+                    Matcher matcher = MEMINFO_PATTERN.matcher(line);
+                    if (matcher.find()) {
+                        String key = matcher.group("key");
+                        String value = matcher.group("value");
+                        if ("MemAvailable".equals(key)) {
+                            available = Long.parseLong(value) * 1024;
+                        }
+                        if ("MemFree".equals(key)) {
+                            free = Long.parseLong(value) * 1024;
+                        }
+                        if ("MemTotal".equals(key)) {
+                            total = Long.parseLong(value) * 1024;
+                        }
+                    }
+                }
+                if (total > 0) {
+                    return Optional.of(new PhysicalMemoryStatus(total, available > 0 ? available : free));
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+
         java.lang.management.OperatingSystemMXBean bean = java.lang.management.ManagementFactory.getOperatingSystemMXBean();
         if (bean instanceof com.sun.management.OperatingSystemMXBean) {
             com.sun.management.OperatingSystemMXBean sunBean =