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Is Mono stable and fast enough? [duplicate]

This question already has answers here:
Is Mono ready for prime time? [closed]
(17 answers)
Closed 8 years ago.
C# looks great because it is a compiled language which seems to run quite well without too much CPU and does not consume too much memory. And StackOverflow and ServerFault are good examples of an MVC/.Net/C# stack that scales.
C# is also interesting because despite being compiled, it still has a lot of advanced features as a language only found on slower interpreted language.
My server being Linux only (Ubuntu 8.04 LTS), I am wondering if installing Mono in place of the .Net framework is a good idea for production use.
I currently do not have any existing applications using .Net but I am interested in using existing frameworks (like MS MVC).

Stable enough and fast enough to do what?
It will have different levels of stability and performance depending on what you want to do, I'm sure. For example, one of my Protocol Buffers unit tests (which uses Rhino.Mocks) manages to make the Mono VM abort with an assertion error - but I have no idea (currently) of whether that would affect anything else I'm doing, or whether it's just related to the form of proxying being used.
I suggest you try it and see.

ASP.Net MVC is now open source. That it is now integrated into MonoDevelop via an add in would suggest that you are likely to get things working.
Given the very new status of this you should expect issues. This blog should be a reasonable starting point for you.
Remember that many ASP.Net MVC tutorials assume you have a sql server back end, this is unlikely to be feasible (given your question) so bear that in mind.

You'll have to judge it on a feature basis. At my current customer we're running a high-volume document processing and delivery system written in .NET 3.5. We have a Linux server that runs Mono with .NET components that take care of the delivery of documents to the outside world, e.g. through FTP. That runs fine in production.
We did run into a problem with the Mono implementation of the .NET FTP component, which forced us to look for other third party .NET components, which solved the problem. So you might run into things like these. But in our case: once we got it to work, it worked just fine and stable.

I think that Mono is REALLY stable and complete.
It brings .NET to *nix World.
In my company I'm leading a project aimed to build an automated machine. This machine is built by different devices that need to be governed using a serial interface (RS232).
The machine exposes a touch screen for user interaction.
One of my responsibilities is to project the logic of the system beyond the GUI application.
I've chose Mono (used for presentation layer) also to build a custom middleware that runs the application business logic.
This middleware is some sort of application server and it's executed in Ubuntu 10.04 LTS.
For now all the system is an advanced prototype, but also the final product will keep its heart in the couple Linux/Mono.
I hope that these considerations could be useful for you.
Regards,
Giacomo

as i had read on mono project wait for MONO 3.0 it will solve the main problem in mono means memory leakages and garbage collectors so before 3.0 we can't say it as stable but it is a life line for developers like us who want to develop platform independent s/w with dot net.

mobile ocr sample code

I was wondering if you can give me sample (or snippet) code in OCR for Mobile Phones because i need to have an idea how to start my project. i know how to code it for the use in desktop PC's but my partner told me that mobile phones has a different platform. We are planning to use .net for mobile on this one.. hope you can help me..:)

It looks like there isn't much for C#/.NET, according to this question. If you have written OCR code yourself using C#, it might work as is on the Compact Framework, or it might be made workable with minor modifications. The Compact Framework is a subset of the full .NET framework, so usually code written specifically for CF will run in regular Windows, but code written for Windows may or may not run in CF, depending upon what functionality has been utilized.
Your partner is sort of right, but there are lots of different platforms for mobile device development, and .NET is definitely one of them (and a good one at that).

Is WPF on Linux (already) possible?

I love programming with .NET, especially C# 3.0, .NET 3.5 and WPF. But what I especially like is that with Mono .NET is really platform-independent.
Now I heard about the Olive Project in Mono. I couldn't find some kind of Beta.
Does it already work? Have any of you made any experiences with it?
Edit: I know about Moonlight. But I want a standalone WPF application. And because of Moonlight I hope WPF on Linux will become true.

You'll have better luck working with Moonlight, which targets the Silverlight API, which is a subset of full WPF.
edit: Sure, Silverlight isn't "intended" for the desktop, but there's no reason why you can't embed a silverlight engine in your application. It's been done before, such as for the Mac NY Times Reader
more edit: see Miguel's post on Standalone Silverlight Applications

Update: Since people keep upvoting this, I want to point out it is long since out of date. Mono got acquired by MS years ago, and their posture regarding open-source has changed, so consider this post obsolete. (As obsolete as the WPF framework itself, heh).
Mono is in a bit of an uncomfortable position when it comes to Microsoft APIs such as Winforms and WPF. A subset of the .Net technology is an ECMA standard, but free implementations of these APIs are probably on shakier legal ground. I believe this was a large factor in the covenant between Novell and Microsoft, which is good for Novell customers. But people who use Mono that aren't customers of Novell aren't protected. For this reason a lot of people in the F/OSS community look askance at Mono despite its technical merits.
For this reason, Gtk# will always be preferred, since it is truly Free. Many people consider it to be superior to Winforms anyway. As far as WPF is concerned, it will almost certainly be a low priority for Novell. They may implement it eventually, but I would expect Moonlight to be the closest you could get for the forseeable future.
Since posting this, Microsoft has extended their covenant to anybody who implements the ECMA 334 & 335 standards.

From the mono website
At this point, the Mono project does
not have plans to implement Windows
Presentation Foundation APIs as
part of the project.
Moonlight is an implementation of silverlight, which is a browser based flash like technology based on a subset of WPF.
In my opinion the choice to not implement WPF is monos biggest mistake. As WPF is fast becoming the default choice for new .net user interfaces. See this blog for more.

There is a library called Silverform SDK that aims to provide cross-platform WPF and Silverlight implementation.
The library is implemented in managed code and currently works with OpenTK and Unity3D as render backends. Major functionality, such as binding, layout, main controls and primitives, has already been implemented (check Unity web player demos here). Initially it has been focused on Unity3d render, while support for standalone Mono applications will be added as a separate build in the future.
Disclaimer: I am one of the developers of the library.

If you check Known bugs of this link(also includes steps needed to install .NET onto Ubuntu)or this you may find that some(may be buggy) version of WPF works on Wine as for now. I did not find any definite test done as for now, but worth to try to run WPF "Hello world".
UPDATE2:
I have run latest IlSpy on latest Wine for Ubuntu 16.04. With 32 bit version of dotnet45 and corefonts installed via winetricks with windows 7 compatibility.
For this time no crashes and all things work fine. Fonts look really good.
IlSpy is shown via WPF and for person who loves programming with .NET is essential tool - the decompiler.
I downloaded latest portable SharpDevelop(build using WPF) with no extra. It started. Failed to create WPF project. Created WinForms. After opening some cs files and evidencing some glitches, tried to type - and it crashed.
UPDATE
I followed steps and got latest ILSpy.exe running on Ubuntu 14.4.
Next items to note:
wine stated that dotnet40 is not supported by 64 configuration, changed to 32 bit
fonts are ugly, but readable
basic functional works fine - I can see decompiled code - which is good enough for some development, but View -> Search and View -> Options -> Display crash.
Conclusion:
WPF on Linux is possible. But need some way to tackle issues.

From the Olive home page:
Olive is unsupported, should be
considered as experimental software,
and since it implements a shifting API
there are no guarantees of any kind
about the stability of the API.
I doubt anyone would have used it in a real project.

Yes, it is possible using NoesisGUI a real-time multi-platform XAML implementation. There are a few games already released using this technology in Linux, like VoidExpanse
Disclosure: I am one of the developers of this product.

I heard a podcast interviewing miguel de icaza (the mono lead) maybe a few weeks ago, so that would have been maybe mid-december 2008, and he said that they had no WPF support at all yet.

Theoretically, a stripped version of WPF COULD be compiled against WinPR or LibWine to run on Linux.
Currently there is no such setup, so someone would need to make one. Hopefully this might change soon.
As of running against or in a full Wine environment, I think that is seriously overkill and will result in too much bloat to be worth making a very small number of additional programs work.

C++ or C# to program mobile barcode device?

I will be developing some applications using mobile barcode scanners and need to choose between C++ and C# for coding on the scanners.
I am considering Intermec's CK31 or similar for the combination of wifi, scanning choices, programmability and user interface options. It runs Windows CE .NET 4.2 according to their spec sheet.
Intermec's Developer Library comes with .Net and C++ SDKs. My previous Win CE 2003 experience is in C++ (MFC GUI, sockets and serial comms). I'm comfortable in C# with WPF and can learn other GUI frameworks if I have to. That gives me freedom to choose a language - any recommendations one way or another?
I am NOT looking for answers advocating C++ over C# as languages in general - my productivity in either is similar and I have enough experience to be able to create complex, robust C++ solutions.
What I would appreciate are war stories or factors to put into our platform evaluation, about programming on these devices. eg: battery life of C# apps vs C++ apps, memory consumption or other environmental impacts of the language choice. If there are specific versions of .Net CE to avoid, that would be a good tip.

I've been designing and developing software for Windows Mobile and Windows CE in C, C++ and C# for quite a few years now. Moreover, I been doing so for Honeywell (formerly Hand Held Products, purchased by Honeywell in 2007) where I've worked on nearly all aspects of the devices, from drivers and services to Line of Business GUIs and utilities.
First of all, I won't tell you one language is better than the other... I probably spend a 50/50 split of my time with each, and each platform definitely has their own place in the mobile development.
I will however, give a suggestion that you likely stay away from any device that runs an OS as old as WinCE 4.2, especially if you are even considering .NET development. The reasoning for this is that 4.2 only has, at most, .NET CF 1.0 embedded in ROM (part of the OS ROM image), meaning that you would require a ~5MB CAB file to install at least .NET CF 2.0 Yes, you could develop with CF 1.0 but, truly, it's not worth the pain of using such an old framework. Most WinCE 5.0 devices these days come with CF (Compact Framework) 2.0 installed in the ROM so I would at least look for that.
On that same vain, you may even want to consider using a device with Windows Mobile 6.0 or 6.1 as they are easy to program with and will always have CF 2.0 pre-installed. In case you're wondering why I have not mentioned CF 3.0 or CF 3.5, it's just because the first Mobile platform to be release with those versions will be Windows Mobile 6.5, which is not out yet. Though you can always install the framework if you want (~8MB CAB).
Granted, WinCE definitely gives you a more "Windows" look and feel to its GUI over its Windows Mobile cousin, so that is all a matter of your programming preference and what your end users want and need.
Regarding kgiannakakis's comments on SDKs being only a thing layer, this is just not true. If you have a proper SDK you should have all of the same access to any devices or drivers that you would in C++ but with the ease of C#. For example, Honeywell provides an extensive SDK for all of our devices in C++, VB and C# and the C# portion of the SDK actually has more functionality than the C++ portion. You will never have to do a P/Invoke with our code from C#.
If you want to take a look at the SDK I'm talking about, it's freely available to download here and has some great examples.
IMHO I would actually consider the provided SDK as more important than the hardware in many cases since, most of the time, the hardware for the devices is pretty much the same. They all have ARM CPUs, WiFi, Bluetooth, Laser or Image based scanners, etc.
Though, I looked at the Intermec link you posted and it doesn't look like that unit actually has a built in scanner...are you using an external scanner hooked to the device?
Take a look at the Honeywell offering if you want here. We've got devices with probably the best imager based bar code scanner in the business, built into all of our units. And we have a rock solid SDK (I should know, I wrote a lot of it). And the SDK provides .NET extremely access to all of the hardware on the device. Ok...I'll stop my sales pitch now.
As for one language over the other...it really all depends on what exactly you want to do.
Drivers and services cannot be written in anything but Native (Win32) C or C++. So .NET is out for anything like that.
C and C++ can absolutely be your friend on mobile devices in terms of keeping things lightweight, since you don't need the whole .NET framework to run the add. Remember, you have a maximum of 32MB of memory for any process (not including DLLs..that's another lecture) so if your application is going to be processing a ton of data, C++ may be the way to go.
One of the major disadvantages I've found to C and C++ on mobile systems, however, is that making a GUI is way harder than it is with .NET Actually, most of the C++ apps I write are completely headless and have no GUI at all... .NET CF does not have WPF (yet), and is stuck with WinForms, but it's really easy to pick up. Pretty much drag and drop in the designer. And also remember, like I mentioned before, that WinCE has a completely different GUI paradigm than Windows Mobile. However, sometimes the Windows Mobile way is kind of nice, since it forces you to keep your GUIs simple and to the point.
Memory consumption can be higher when using .NET, but not always. For one, having a device with the version of the CF you are going to use stored in ROM will mean that you will generally have no more memory used on a .NET application vs the equivalent C++ app. In some cases, .NET will even use less memory. For example, a .NET app vs a C++ app that uses MFC can often use less memory because the C++ app has to load up the MFC framework (since it isn't already loaded by the OS...).
Also, since C# is managed, you will often end up with less memory usage because the garbage collector is freeing up memory that you may have forgotten to do in a C++ app.
Execution speed on more modern devices is generally no different between the two. Granted, you will always have little parts of each language where one will be faster than the other, but .NET is mature enough at this point that the speed is not really a concern. I have programmed extremely fast applications with highly interactive, animated GUIs that ran just fine on a device with 128MB RAM and a 420MHz ARM CPU. I even wrote one app that I had to slow down because it was calling into a native DLL via P/Invoke and the .NET portion was essentially getting "Impatient."
I have never seen any issues with battery life in one language vs the other. But I've never specifically tested for it either.
I really think that, in the end, it still comes down to the SDK that comes with your device of choice. If it has poor .NET support then you will find your self doing a lot of extra work getting everything to work, in which case I would go with C++. But if it has great .NET support (like the one I work on) you will find yourself with a lot less work and probably get the job done significantly faster.
Also, remember that it's not just the SDK of the hardware vendor you have to take into account. While you need that specific SDK as each device is different (i.e. the SDK I linked to earlier will not work on that Intermec device) all of the non-hardware related OS stuff is pretty much standard across the board, which is where the Windows Mobile or Windows CE SDK from Microsoft comes in. Their C++ support is pretty good, but they are really pushing all things .NET these days, so as updates are made to the OS, less updates are made to the C++ SDK and much more functionality now relies on using .NET Not that you couldn't do it in C++, it's just that they haven't done a lot of the work for you that they did do in the .NET SDK.
Ok...that was long, but I was trying to dump the finer parts of my years of experience into one thing. I hope it made sense.

The answer to your question has to do with the type of your application. If your application is mainly around communicating with the hardware and only a thin layer of business logic and User Interface is needed, then C++ would be a better choice. To interact with the scanners you need to talk to a driver. This is better and faster achieved with C++. The .NET SDK will actually be a wrapper of C++ code using a ton of P/Invoke, which makes the code performing less faster.
If on the other side your application requires a significant business layer and/or a User Interface, then .NET (and specifically C#) is a better option. In that case the productivity gains far out weight the performance gains of C++.
Another important factor is the type of the devices the application is going to be deployed to. Are you targeting Windows Mobile devices only? Then .NET is a safe option. For Windows CE devices you need to investigate whether the compact framework is pre-installed or not. Also, some Windows CE devices may not support all .NET namespaces.
Finally, I recommend reading Mobile Architecture Pocket Guide, which is a recent document about architectural decisions for mobile applications.

First I'll strongly echo Adam's recommendation against running anything based on CE .NET 4.2 at this point for essentially the same reason. At this point it's an ancient version of the OS and unless you are getting the terminal for free it's not worth it and if you choose to do C# development the download of the CAB to run .NET 2 is just painful.
We've developed a lot of applications for both Motorola(Symbol) and Intermec devices. The current set of APIs for both of them work reliably so I'd worry more about the suitability of the device than the specific APIs. They also both provide reasonable sample programs that make it easy to cut and paste a solution.
I have noticed one other big difference between Motorola and Intermec. On the Intermec devices I've worked with (in C#), it takes about a second for the decoder for each symbology to be loaded. This typically isn't a big deal if you use a limited number of symbologies and setup the scanner at the start of the application, but can cause significant delays if you change the decoders(symbologies) within the application.

I've been developing for about 15 years. Approx 5 years in C++ and 3 years in C# (which currently is my language of choice). In C++ I always used stdlib, and sometimes boost.
I have cut my development time with a third since I switched from c++ to c#. That was done because of a couple of things (nothing scientific, just my opinons):
.Net is a more complete framework and easier to use than stdlib and boost combined.
C# has a better structure which make easier to read others code and to code.
Unit testing in .Net is light years from unit testing in C++, especially with Resharper and xUnit (xUnit got clean syntax, resharper let's you test specific test methods directly inside dev studio).
I mostly code servers, GUI programming should be even faster.

Making a C#/Winform application cross-platform - should I use AIR, Mono, or something else?

I have an app that I've written in C#/WinForms (my little app). To make it cross-platform, I'm thinking of redoing it in Adobe AIR. Are there any arguments in favor of WinForms as a cross-platform app? Is there a cross-platform future for Winforms (e.g., Mono, etc.)? Suggestions for cross-platform UI development?
By cross-platform I mean, currently, Mac OSX, Windows and Linux.
This question was asked again and answered with better success.

As far as my experience in Flex/AIR/Flash actionscripting goes, Adobe AIR development environment and coding/debugging toolsets are far inferior to the Visual Studio and .NET SDK as of the moment. The UI toolsets are superior though.
But as you already have a working C# code, porting it to ActionScript might requires a redesign due to ActionScript having a different way of thinking/programming, they use different primitive data types, for example, they use just a Number instead of int float double etc. and the debugging tools are quiet lacking compared to VS IMO.
And I heard that Mono's GtkSharp is quiet a decent platform.
But if you don't mind the coding/debugging tooling problems, then AIR is a great platform. I like how Adobe integrates the Flash experience into it e.g. you can start an installation of AIR application via a button click in a flash movieclip, that kind of integration.

I'm thinking of redoing it in Adobe AIR
Not having spent much time with AIR, my personal opinion is that it is best for bringing a webapp to the desktop and provide a shell to it or run your existing flash/flex project on the desktop.
Btw, if you don't know ActionScript, I mean its details, quirks, etc, don't forget to factor in the time it will take googling for answers.
Are there any arguments in favor of WinForms as a cross-platform app?
Is there a cross-platform future for Winforms (e.g., Mono, etc.)?
It's always hard to predict what will happen, but there is at least one project (Plastic SCM) I know of which uses Mono Winforms on Win, Mac and Linux, so it is certainly doable. However, they say they built most of their controls from the ground up (and claim they want to release them as open source, but not sure if or when), so you will need to put in some work to make things look "pretty".
I played with Winforms on non-windows platforms and unfortunately, it isn't exactly "mature" (especially on Mac). So what you get out of the box may or may not be sufficient for your needs.
If you decide a desktop app is not the best way to provide a cross-platform solution, you can always take your business logic written in C# and create either a full-blown webapp with ASP.NET or go with Silverlight, so many other options exist with C#.

WinForms are fully supported by Mono, so they are cross-platform.

Why would you go with Air?
Use GTK#, and you have a cross platform forms engine and you get to keep your C# code.

Well I think the only way to for cross-platform reliably with C# is Microsoft Silverlight, but is not really WinForms, and browser-based. Other than that, yes Mono is a chance.

If you want to use the .net Framework, Microsoft Silverlight is a good (the only?) choice. The browser does a good job as a shell, but you could also write your own application shell for it. For example, Scott Handelman mentions the NY Times Reader written in Silverlight and hostet on Cocoa on a Mac.

I don't think there is a future for WinForms at all. Since it appears to have been a stop-gap solution even in MSFT world ( a very thin wrapper around Win32). And virtually no changes seem to have been made to System.Windows.Forms in both .NET 3.0 and 3.5
</speculation>
I would use Java or Air.

I think that as long as you make sure that the business logic code you write is cross-platform (i.e. using backslashes in paths only works on Windows - forward slashes works on all OS's), then Mono shouldn't have major problems running an unmodified WinForms program. Just make sure you test for graphical glitches.

I asked a similar question last week. I've been using Mono all along, and have had no issues running the applications I compile to IL to run on SuSE linux (I usually run KDE) or windows, however, I've not gone out and got a mac yet to test it on. I will be soon, though, probably with in a couple weeks. But all and all development in Mono has been very good at creating application that will run on multiple platforms.