X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;f=src%2Fjalview%2Fbin%2FMemorySetting.java;fp=src%2Fjalview%2Fbin%2FMemorySetting.java;h=b3bae2df110ec6933c89891f1817859cf41bd304;hb=b419d3b17606d478c234678487ff34d97bfa83cc;hp=0000000000000000000000000000000000000000;hpb=b0716c75367a82443cd516ef3ea08708dacd92e9;p=jalview.git

diff --git a/src/jalview/bin/MemorySetting.java b/src/jalview/bin/MemorySetting.java
new file mode 100644
index 0000000..b3bae2d
--- /dev/null
+++ b/src/jalview/bin/MemorySetting.java
@@ -0,0 +1,51 @@
+package jalview.bin;
+
+import java.lang.management.ManagementFactory;
+import java.lang.management.OperatingSystemMXBean;
+
+public class MemorySetting
+{
+  public static final long leaveFreeMinMemory = 536870912; // 0.5 GB
+
+  public static final long applicationMinMemory = 536870912; // 0.5 GB
+
+  protected static long getPhysicalMemory()
+  {
+    final OperatingSystemMXBean o = ManagementFactory
+            .getOperatingSystemMXBean();
+
+    try
+    {
+      if (o instanceof com.sun.management.OperatingSystemMXBean)
+      {
+        final com.sun.management.OperatingSystemMXBean osb = (com.sun.management.OperatingSystemMXBean) o;
+        return osb.getTotalPhysicalMemorySize();
+      }
+    } catch (NoClassDefFoundError e)
+    {
+      // com.sun.management.OperatingSystemMXBean doesn't exist in this JVM
+      System.out.println("No com.sun.management.OperatingSystemMXBean");
+    }
+
+    // We didn't get a com.sun.management.OperatingSystemMXBean.
+    return -1;
+  }
+
+  public static long memPercent(int percent)
+  {
+    long memPercent = -1;
+
+    long physicalMem = getPhysicalMemory();
+    if (physicalMem > applicationMinMemory)
+    {
+      // try and set at least applicationMinMemory and thereafter ensure
+      // leaveFreeMinMemory is left for the OS
+      memPercent = Math.max(applicationMinMemory,
+              physicalMem - Math.max(physicalMem * (100 - percent) / 100,
+                      leaveFreeMinMemory));
+    }
+
+    return memPercent;
+  }
+
+}