Memory leak using EmbedHostObject #65
Description
Accessing properties of registered host objects leak memory
The following examples registers a tiny host object with one property and one basic method within. Using a docker runtime with 128MB, memory will grow quickly and process will die after about 100000 calls reaching its memory limit. If the method doSomething is moved up to the class Native, everything works fine and the process stays at stable 27MB memory usage.
using System;
using JavaScriptEngineSwitcher.ChakraCore;
using JavaScriptEngineSwitcher.Core;
public class Native {
public SomeClass SomeObject { get; set; } = new SomeClass();
}
public class SomeClass {
public string doSomething(double i) => "SomeValue@" + i;
}
class Program
{
static void Main(string[] args)
{
var newEngine = new ChakraCoreJsEngine();
newEngine.EmbedHostObject("native", new Native());
newEngine.Execute(@"function testFunction(i) {
return native.SomeObject.doSomething(i);
}");
for (int i=0; i < 1000000; i++) {
var result = newEngine.CallFunction("testFunction", new object[] { (double)i });
if (i % 10000 == 0) Console.WriteLine($"Called test #{i}, result was {result}");
}
}
}In this simple example we can work around the leak pre-evaluating the property.
newEngine.EmbedHostObject("_native", new Native());
newEngine.Execute(@"var native = { SomeObject: _native.SomeObject };");