Has anyone tried to port Mono to RTEMS

[Russell Haley]

Mono runs fine on millions of Android devices. Application level
processors and the sort (i.e. the BBB) are fine. I would think 512 MB
of memory would be a pretty safe lower limit for small applications.
However, I question using a framework with a large amount of memory
usage and an active garbage collection system on an RTOS? I just
finished reading a post where they admit in the older frameworks that
some operations can cause process delays of up to 120 milliseconds
(they were discussing the new garbage collection in 5.0 so didn't mind
admitting the poor performance). I'm just an amateur so I'd love to
hear a professional take on that.

My favoured solution now is Lua. It's very small and lightweight and
hooks neatly into C for high performance needs like monitoring inputs.
Peter MacDonald, who is known for inventing the first Linux
distribution (wikipedia SLS Linux), just created a similar type of
shell language using a flavour of JavaScript called (unsurprisingly)
JavaScript Interactive Shell (Jsish). The site is http://jsish.org/.
It uses limited type checking and comes with built in support for
websockets, sqlite and a couple of other nice tools. It also has a
lightweight debugger. Very cool.

I'll also cross link something from the Lua mailing list that may be
of interest on this list. It's a discussion of using hardware to
accelerate type checking in dynamic languages to increase performance.

https://pllab.github.io/papers/Typed-Architectures-Architectural-Support-for-Lightweight-Scripting/KIM-ET-AL_typed-architectures-architectural-support-for-lightweight-scripting_2017_ASPLOS.pdf

Sweet. And my rtems clone is finished. :D

Russ

On Thu, May 25, 2017 at 12:31 AM, xuelin.tian at qkmtech.com
<xuelin.tian at qkmtech.com> wrote:
> Hi Russell,
> I have another thing to ask you.
> Have you ever done some assessment of resource occupancy? Like how much
> memory would Mono use, generally, and CPU and so on...
>
> ________________________________
> Best wishes,
> xuelin.tian at qkmtech.com
>
>
> From: Russell Haley
> Date: 2017-05-25 08:24
> To: xuelin.tian
> CC: users
> Subject: Re: Has anyone tried to port Mono to RTEMS
> On Wed, May 24, 2017 at 9:52 AM, xuelin.tian <xuelin.tian at qkmtech.com>
> wrote:
>>
>> Hi Russell,
>> thank you for your reply. It helps a lot.
>> Could you share me the link or hub of this build system, that I can try to
>> build Mono on my rtems based on ARM?
>
> FreeBSD uses a system called  ports that builds a piece of software
> configured for FreeBSD. The system is well documented in the FreeBSD
> handbook:
> https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/ports.html
>
> The port you are looking for is:
> http://www.freshports.org/lang/mono/
>
> Effectively, if you have set up ports on your FreeBSD computer, you
> can then type a simple command to build it. The command to build can
> usually be found on the freshports.org page for that package[1]. In
> this instance it is:
>
> cd /usr/ports/lang/mono/ && make #--> No installation on rootfs
> cd /usr/ports/lang/mono/ && make install clean
>
> If you want to make changes to the port, I recommend using subversion
> to download the ports tree because if you use the standard method, an
> update to the ports tree will overwrite your changes. This method is
> also documented in the handbook at
> https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/ports-using.html
>
> Now, be aware that this can also all be done from pulling the Mono
> repository from GitHub.com and building it yourself on any platform
> you choose.
>
> [1] I don't know anything about cross compiling for RTEMS as a limited
> amount of free time has rendered me a sideline spectator for RTEMS at
> this point. Note that cross compiling for ARM can be somewhat more
> involved. I can dig up some stuff if necessary.
>
> Russ
>
>
>> ------------------ Original ------------------
>> From:  "Russell Haley"<russ.haley at gmail.com>;
>> Date:  Wed, May 24, 2017 11:46 PM
>> To:  "xuelin.tian"<xuelin.tian at qkmtech.com>; "users"<users at rtems.org>;
>> Subject:  Re: Has anyone tried to port Mono to RTEMS
>>
>> Sorry I should have also noted that mono and mono develop are well
>> supported on FreeBSD 10.3+ on mono 4.2 and up. I think the latest is 4.6?
>> Check freshports.org. Monodevelop works too iirc. TrueOS is a good way to
>> get started.
>>
>> Russ
>>
>> Sent from my BlackBerry 10 smartphone on the Virgin Mobile network.
>> From: xuelin.tian at qkmtech.com
>> Sent: Tuesday, May 23, 2017 6:58 PM
>> To: users at rtems.org
>> Subject: Has anyone tried to port Mono to RTEMS
>>
>> Dear all,
>> Is that possible to port Mono to RTEMS? Has anyone tried this before?
>> As I notice that there is an open project in RTEMS projects.
>>
>> ________________________________
>> Best wishes,
>> xuelin.tian at qkmtech.com
>>