diff --git a/SystemInformation.cxx b/SystemInformation.cxx
index 0ee02bd63ecec3a96e025b83edcd2128e152eea6..0c9885fac13e9f9f555855fac50a089a3180dda5 100644
--- a/SystemInformation.cxx
+++ b/SystemInformation.cxx
@@ -3416,6 +3416,16 @@ int SystemInformationImplementation::QueryMemory()
       }
     }
   return 0;
+#elif defined(_AIX)
+  long c = sysconf(_SC_AIX_REALMEM);
+  if (c <= 0)
+  {
+    return 0;
+  }
+
+  this->TotalPhysicalMemory = c / 1024;
+
+  return 1;
 #else
   return 0;
 #endif