Taritsyn/JavaScriptEngineSwitcher

Memory leak using EmbedHostObject

ralfkahlert opened this issue · 8 comments

ralfkahlert commented

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 };");
Taritsyn commented

Hello!

Thanks for information. I will deal with this problem in 2019.

ralfkahlert commented
Taritsyn commented

Thanks!

Taritsyn commented

Hello, Ralf!

Try to upgrade to version 3.0.1.

ralfkahlert commented

Hi! Looks good, i'll run some integration tests tomorrow watching mem usage.

Thanks
Ralf

Taritsyn commented

Hello, Ralf!

What results were obtained during the tests? By the way, in version 3.0.2 was made additional optimizations.

ralfkahlert commented
Taritsyn commented

OK, then I close this issue.