XobotOS: Android Build on C# Instead of Java

Don't know about other people, but using machine translation to port Android to C# is cool. I could do without the hype and exaggeration. Mono has always been slower than Microsoft's CLR and the GC has always performed worse than Microsoft CLR and Sun Hotspot. The early decision to NOT use generational GC was a huge mistake and smells of NIH syndrome. Mono is "maturing", but I wouldn't say it is more mature than Dalvik. Judging the maturity of a software product based on superficial criteria like "age" is flawed.

The most mature VM today is Azul's. Nitpicking aside, it is nice to have C# as an option.

I don't think it is appropriate to consider compare Mono to .NET or Hotspot in this context, as they are only claiming to be better than Dalvik. And they have been working on their VM a lot longer than Google has, so their claim is at least plausible.

And really, what do we know about Dalvik? All I personally know is the uses a register-based VM instead of a stack based VM like Java and .NET, which means a lot of the research into that area cannot be reused. It's JIT compiler is less than two years old (it's birthday is the 20th), and I heard (unconfirmed) claims that Dalvik does not yet have a generational garbage collector.

If you show me evidence otherwise I'll believe you, but right now the guys at Mono are only source of expert opinion on the matter.

I agree Mono has been around longer than Dalvik. I have no proof Dalvik is more or less mature than Mono. My point is that using age as the only basis of judging "maturity" is flawed at best. Only real way to know would be to test it under a wide variety of workloads and gather GC statistics to characterize the performance. Even then, there's going to be certain types of workloads that each is good at. Just like JVM and CLR each have sweet spots.

The Mono guys are experts at Mono, but it would be a stretch to claim they are experts in Dalvik. To really get a full and complete picture would be to have both teams do an exhaustive test and compare notes.

My original point is Mono's hype is silly. The project is neat, but there's no need for all that hype.

..but to use the word 'mature' for Mono (or the CLR for that matter) shows a real lack of sense for reality. Would be great if they matured though, since IL is in fact more mature as bytecode.

In general, JIT compilers start by translating a stack machine model into a register-based model, and that is (according to the Hotspot JVM developers) a relatively simple thing.

And really, what do we know about Dalvik?

Try it. Perhaps you will have more luck but I haven't seen much on the Dalvik runtime itself.

Mono, on the other hand, has been quite vocal about their work. They regularly talk about where the VM is weak and what they are doing to improve it.

This is not unexpected. Mono is a choice, so it needs advertising. Dalvik is a default, if you choose Android you get it whether you want it or not.

Try it. Perhaps you will have more luck but I haven't seen much on the Dalvik runtime itself.

Using some simple benchmarks comparing generic support in Java and C# they were able to show some significant improvements.

for(int i=1; i<=n; ++i) {
  hashtable.put(i, 1.0f / i);
}

Wow, all that hype for so little. I'd like to see something substantial like an actual application that a real person would want to use. Hopefully InfoQ won't make the same mistake again.

You got Peter Lin that throws a fit anything Mono-related comes up and Cameron (who works for Oracle) who has been trolling against .NET on the server side for years.

Don't worry guys, it's been thrown on Github and it's basically been said that Xamarin isn't going to pursue anymore out of it.

Dan,

Lots of bitterness from the usual suspects

I have zero bitterness about Mono. I just don't like hype, no matter where it comes from. When spring hypes stuff, I complain. When other projects have silly hype, I complain. On the contrary, I am happy that Mono exists. It means I can write C# app and deploy it on Linux. I've used it in the past for my open source XML Schema compiler, which I wrote in C#. It works perfectly fine in CLR or Mono. I also have a RETE rule engine for C#.

Just because I don't blindly jump for joy when some project does a hype PR release, doesn't mean I dislike the project. I do play devil's advocate and "throw a fit" as you say. I've been known to "throw a fit" against CEP hype, business rules hype, data grid hype and every other retarded PR release.

I just call it as I see it. I don't feel it's fair to claim Cameron is trolling.

I on the other hand definitely troll, especially when someone says "spring is light, maven is awesome and x will solve all your problems." On the other hand, when a PR release is grounded and doesn't resort to BS non-sense, I generally post positive comments.

"Unlike Sun with Java, Microsoft submitted C# and the .NET VM for standardization to ECMA ..."

On Wikipedia it says: "As of December 2010, no ECMA and ISO/IEC specifications exist for C# 3.0 4.0, and 5.0."

Anyone knows about the current status?

Peter, Dan must be thinking about your feelings about Maven. :p

I have been following posts by Cameron and Peter for years. I don't remember this being the case with Mono OR .NET with them. Not everyone likes everything about everything but that does not constitute what you describe. As Cameron said, "his" product supports .NET and I think Peter has an opensource one that does.

Guilty as charged! I have a love & hate relationship with maven. I love to hate it and hate it passionately. I have zero objectivity when it comes to maven :)