[WIP] Report memory minus reserved memory

cosmic-agent/src/main/java/com/cloud/agent/resource/kvm/LibvirtComputingResource.java

@@ -511,7 +511,8 @@ public CpuStat getCpuStat() {
     }
 
     public MemStat getMemStat() {
-        return this.memStat;
+        final long dom0MinMem = getHostReservedMemMb();
+        return new MemStat(dom0MinMem);
     }
 
     public VirtualRoutingResource getVirtRouterResource() {

cosmic-agent/src/main/java/com/cloud/agent/resource/kvm/wrapper/LibvirtGetHostStatsCommandWrapper.java

@@ -25,15 +25,12 @@ public Answer execute(final GetHostStatsCommand command, final LibvirtComputingR
         final MemStat memStat = libvirtComputingResource.getMemStat();
 
         final double cpuUtil = cpuStat.getCpuUsedPercent();
-        memStat.refresh();
-        final double totMem = memStat.getTotal();
-        final double freeMem = memStat.getAvailable();
 
         final Pair<Double, Double> nicStats = libvirtComputingResource.getNicStats(
                 libvirtComputingResource.getPublicBridgeName());
 
         final HostStatsEntry hostStats = new HostStatsEntry(command.getHostId(), cpuUtil, nicStats.first() / 1024,
-                nicStats.second() / 1024, "host", totMem, freeMem, 0, 0);
+                nicStats.second() / 1024, "host", memStat.getTotal() /1024, memStat.getAvailable() /1024, 0, 0);
         return new GetHostStatsAnswer(command, hostStats);
     }
 }

cosmic-agent/src/test/java/com/cloud/agent/resource/kvm/LibvirtComputingResourceTest.java

@@ -880,8 +880,8 @@ public void testGetHostStatsCommand() {
         when(this.libvirtComputingResource.getMemStat()).thenReturn(memStat);
         when(this.libvirtComputingResource.getNicStats(Matchers.anyString())).thenReturn(new Pair<>(1.0d, 1.0d));
         when(cpuStat.getCpuUsedPercent()).thenReturn(0.5d);
-        when(memStat.getAvailable()).thenReturn(1500.5d);
-        when(memStat.getTotal()).thenReturn(15000d);
+        when(memStat.getAvailable()).thenReturn(1500L);
+        when(memStat.getTotal()).thenReturn(15000L);
 
         final LibvirtRequestWrapper wrapper = LibvirtRequestWrapper.getInstance();
         assertNotNull(wrapper);

cosmic-common/src/main/java/com/cloud/utils/linux/MemStat.java

@@ -12,25 +12,32 @@ public class MemStat {
     protected static final String FREE_KEY = "MemFree";
     protected static final String CACHE_KEY = "Cached";
     protected static final String TOTAL_KEY = "MemTotal";
+    long reservedMemory;
 
-    private final Map<String, Double> memStats = new HashMap<>();
+    private final Map<String, Long> memStats = new HashMap<>();
 
     public MemStat() {
+        this(0);
     }
 
-    public Double getTotal() {
-        return memStats.get(TOTAL_KEY);
+    public MemStat(long reservedMemory) {
+        this.reservedMemory = reservedMemory;
+        this.refresh();
     }
 
-    public Double getAvailable() {
+    public Long getTotal() {
+        return memStats.get(TOTAL_KEY) - reservedMemory;
+    }
+
+    public Long getAvailable() {
         return getFree() + getCache();
     }
 
-    public Double getFree() {
-        return memStats.get(FREE_KEY);
+    public Long getFree() {
+        return memStats.get(FREE_KEY) - reservedMemory;
     }
 
-    public Double getCache() {
+    public Long getCache() {
         return memStats.get(CACHE_KEY);
     }
 
@@ -48,7 +55,7 @@ protected void parseFromScanner(final Scanner scanner) {
         while (scanner.hasNext()) {
             final String[] stats = scanner.next().split("\\:\\s+");
             if (stats.length == 2) {
-                memStats.put(stats[0], Double.valueOf(stats[1].replaceAll("\\s+\\w+", "")));
+                memStats.put(stats[0], Long.valueOf(stats[1].replaceAll("\\s+\\w+", ""))  * 1024L);
             }
         }
     }

cosmic-common/src/test/java/com/cloud/utils/linux/MemStatTest.java

@@ -2,37 +2,57 @@
 
 import java.util.Scanner;
 
+import org.junit.Assert;
+import org.junit.Test;
 import org.junit.Assert;
 import org.junit.Test;
 
+import java.util.Scanner;
+
 public class MemStatTest {
+    final String memInfo = "MemTotal:        5830236 kB\n" +
+            "MemFree:          156752 kB\n" +
+            "Buffers:          326836 kB\n" +
+            "Cached:          2606764 kB\n" +
+            "SwapCached:            0 kB\n" +
+            "Active:          4260808 kB\n" +
+            "Inactive:         949392 kB\n";
+
     @Test
     public void getMemInfoParseTest() {
-        final String memInfo = "MemTotal:        5830236 kB\n" +
-                "MemFree:          156752 kB\n" +
-                "Buffers:          326836 kB\n" +
-                "Cached:          2606764 kB\n" +
-                "SwapCached:            0 kB\n" +
-                "Active:          4260808 kB\n" +
-                "Inactive:         949392 kB\n";
-
         MemStat memStat = null;
         try {
             memStat = new MemStat();
-        } catch (final RuntimeException ex) {
+        } catch (RuntimeException ex) {
             // If test isn't run on linux we'll fail creation of linux-specific MemStat class due
             // to dependency on /proc/meminfo if we don't catch here.
             // We are really only interested in testing the parsing algorithm and getters.
             if (memStat == null) {
                 throw ex;
             }
         }
-        final Scanner scanner = new Scanner(memInfo);
+        Scanner scanner = new Scanner(memInfo);
+        memStat.parseFromScanner(scanner);
+
+        Assert.assertEquals(memStat.getTotal(), Long.valueOf(5970161664L));
+        Assert.assertEquals(memStat.getAvailable(), Long.valueOf(2829840384L));
+        Assert.assertEquals(memStat.getFree(), Long.valueOf(160514048L));
+        Assert.assertEquals(memStat.getCache(), Long.valueOf(2669326336L));
+    }
+
+    @Test
+    public void reservedMemoryTest() {
+        MemStat memStat = null;
+        try {
+            memStat = new MemStat(1024);
+        } catch (RuntimeException ex) {
+            if (memStat == null) {
+                throw ex;
+            }
+        }
+        Scanner scanner = new Scanner(memInfo);
         memStat.parseFromScanner(scanner);
 
-        Assert.assertEquals(memStat.getTotal(), Double.valueOf(5830236));
-        Assert.assertEquals(memStat.getAvailable(), Double.valueOf(2763516));
-        Assert.assertEquals(memStat.getFree(), Double.valueOf(156752));
-        Assert.assertEquals(memStat.getCache(), Double.valueOf(2606764));
+        Assert.assertEquals(memStat.getTotal(), Long.valueOf(5970160640L));
     }
-}
+}