Ensure we never set more memory than swap for containers

src/system.js

@@ -219,7 +219,10 @@ async function getMemoryAllocation(limit) {
         ratio = Math.round(pc * 10) / 10; // a simple ratio
     }
 
-    return Math.round(Math.round(limit * ratio) / 1048576) * 1048576; // nearest MB
+    const memoryAllocation = Math.round(Math.round(limit * ratio) / 1048576) * 1048576; // nearest MB
+
+    // make sure we never overshoot if the ratio is quite far off (high RAM low swap)
+    return memoryAllocation > limit ? limit : memoryAllocation;
 }
 
 async function getDiskUsage() {