src/jalview/bin/MemorySetting.java

   1 package jalview.bin;
   2
   3 import java.lang.management.ManagementFactory;
   4 import java.lang.management.OperatingSystemMXBean;
   5
   6 public class MemorySetting
   7 {
   8   public static final long leaveFreeMinMemory = 536870912; // 0.5 GB
   9
  10   public static final long applicationMinMemory = 536870912; // 0.5 GB
  11
  12   protected static long getPhysicalMemory()
  13   {
  14     final OperatingSystemMXBean o = ManagementFactory
  15             .getOperatingSystemMXBean();
  16
  17     try
  18     {
  19       if (o instanceof com.sun.management.OperatingSystemMXBean)
  20       {
  21         final com.sun.management.OperatingSystemMXBean osb = (com.sun.management.OperatingSystemMXBean) o;
  22         return osb.getTotalPhysicalMemorySize();
  23       }
  24     } catch (NoClassDefFoundError e)
  25     {
  26       // com.sun.management.OperatingSystemMXBean doesn't exist in this JVM
  27       Cache.log.error("No com.sun.management.OperatingSystemMXBean");
  28     }
  29
  30     // We didn't get a com.sun.management.OperatingSystemMXBean.
  31     return -1;
  32   }
  33
  34   public static long memPercent(int percent)
  35   {
  36     long memPercent = -1;
  37
  38     long physicalMem = getPhysicalMemory();
  39     if (physicalMem > applicationMinMemory)
  40     {
  41       // try and set at least applicationMinMemory and thereafter ensure
  42       // leaveFreeMinMemory is left for the OS
  43       memPercent = Math.max(applicationMinMemory,
  44               physicalMem - Math.max(physicalMem * (100 - percent) / 100,
  45                       leaveFreeMinMemory));
  46     }
  47
  48     return memPercent;
  49   }
  50
  51 }