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Is it possible to build a production web application using MagLev for ruby? [closed]

I'm a fan of Rails and ruby in general, and may embark upon building enterprise applications for financial institutions. I really like the idea of maglev, and wonder whether it's worth consideration. I haven't found much information as to whether maglev is being used in production in the wild, let alone for a high-security purpose.

Has anyone successfully deployed mission-critical applications using MagLev? If so, can you provide details about your experience and maybe name the application?

How can I search a Ruby Maglev array of objects?

How can I search a maglev array of objects? Maglev is great but it doesn't seem to have any querying capabilities. Are there any external libraries for this?

Does an (experimental) class browser exist for Ruby?

Does an (experimental) class browser exist for Ruby?

I am talking about a class browser/editor combination similar to that of most Smalltalk implementations (i.e. focused on [runtime] classes/objects instead of .rb files)

P.S.: it looks like pry is already able to do a lot of the things that would be needed by a smalltalk style class browser? https://speakerdeck.com/u/rahult/p/pry-an-irb-alternative-on-steroids

P.S.2: Looks like the Seaside Smalltalk framework has a web browser based class browser

P.S.3: MagLev/Webtools is the closest I have found yet:

P.S.4: Apparently http://tibleiz.net/code-browser/index.html has Ruby support and is able to present a Smalltalk like class browser:

How can I run Rails on Maglev?

How can I run Rails on Maglev? It seems that it can run Sinatra, but not full blown Rails.

Can Jekyll run on MagLev?

MagLev tries to be compatible with ruby 1.8.7

So it seems to me that Jekyll should be able to run on it...

And based on this previous question, seems that even some rails applications can run on it...

• But has anyone actually tried it?
• What were the problems you had?
• If you haven't tried it, do you anticipate any major problems?

TIA

How can I run maglev-irb with an alternate stone?

Now that rvm seams to handle maglev with ease I wanted to start experimenting with an image different from the standard maglev image. I created a new image using

rake stone:create[experimental]

I could now run code in a VM connected to that stone using

maglev-ruby --stone experimental -e <code>

as expected and it reported the expected stone_name. However I could not get maglev-irb to run with a similar option, judging from the usage info they do not seem to be supported. Trying

maglev-irb --stone experimental

anyway results in an error like

ERROR 2730 , a NameError occurred (error 2730), , global $@ is a read-only variable (NameError)

Maybe there is a less obvious way I am missing? It would really be convenient to play around with maglev features interactively without destroying the default VM in the process.

Do I need to allow the application "stoned" to accept incoming networking connections?

I recently turned my firewall on, and while running multiple rubies, I got the question

Do you want the application "stoned" to accept incoming network connections?

Clicking Deny may limit the application's behaviour. This setting can be changed in the Firewall pane of Security preferences.

After some googling, I worked out it wasn't a malicous app (and definitely not this stoned!), but maglev (presumably "stoned" being "stone daemon").

Unless I'm serving web content or otherwise acting over the network, do I need to enable "stoned"?

How can I install Maglev with rvm on Mac OS X Lion?

I am trying to install Maglev on Mac OS X Lion with rvm, but running

rvm install maglev

as instructed on the github page only yields a 404 error:

curl: (22) The requested URL returned error: 404
ERROR: The requested url does not exist: 'http://glass-downloads.gemstone.com/maglev/MagLev-26852.Darwin-i386.tar.gz'

which does not seem too helpful, as it just points out that the respective file does not exist on the gemstone server. Google does not seem to know about this, so I thought about asking a question here. However, before doing so I tried some more and and got a little further running

 rvm install maglev-head

as mentioned in some blog posts. This finally finds an appropriate file, downloads a bunch of things and starts to compile. It starts to look really well at a point where it says

 Installing maglev to /[user-dir]/.rvm/rubies/maglev-head

in green, but unfortunately it does not get much further. The installation hangs after saying

Creating default 'maglev' repository.
Generating maglev HTML documentation
Generating smalltalk FFI.

or at least it takes forever (more than 30 minutes) without saying anything.

Stopping the installation at this point still looks promising giving me

$ rvm list

rvm rubies

   maglev-head [ x86_64 ]

but unfortunately

rvm use maglev-head

results in

startstone[Info]: Starting Stone repository monitor 'maglev'.

startstone[Error]: Stone process (id=61119) has died.
startstone[Error]: Examine '/[user-dir]/.rvm/rubies/maglev-head/log/maglev/maglev.log' for more information.  Excerpt follows:

without displaying an excerpt and even without stopping. Actually the log file does exist and has a few error messages, the most telling seems to be

GemStone is unable to open the file !TCP@localhost6#dbf!/[user-dir]/.rvm/rubies/maglev-head/data/maglev/extent/extent0.ruby.dbf

but the directory does exist, it would just be the file that is missing, and I would expect the server to create that one on an new image. Still, the situation does not look too bad as i get

which irb

giving me

/[user-dir]/.rvm/rubies/maglev-head/bin/irb

but when I try to start up irb I get

maglev-ruby: [Error] The MagLev server "maglev" is not running.
To fix this run "rake maglev:start" before running maglev-ruby.

but if I call the rake task as instructed I again get

maglev-ruby: [Error] The MagLev server "maglev" is not running.
To fix this run "rake maglev:start" before running maglev-ruby.

putting me in a recursive causality loop. Trying to start the maglev server by hand using

 maglev start

as I did on a previous installation using the shell scripts does not work either, giving me

 startstone[Info]: Starting Stone repository monitor 'maglev'.

 startstone[Error]: Stone process (id=61400) has died.
 startstone[Error]: Examine '/[user-dir]/.rvm/rubies/maglev-head/log/maglev/maglev.log' for more information.  Excerpt follows:

again without displaying an excerpt and hanging.

Any help would be appreciated as Maglev looks like a really promising piece of infrastructure.

How to use prawn on maglev

Being new to maglev I wanted to start with a small, but still useful example. So i decided to start moving the ruby classes I use to generate my invoices to maglev. However I ran in an unexpected problem using the (excellent) prawn PDF-library.

Being on rvm I generated a gemset for the application which is setup in a .rvmrc for the invoice directory. It gets used when I cd into it:

Using /Users/patru/.rvm/gems/maglev-head with gemset invoice

When I install prawn everything starts out fine, the gem seems to be installed and the ri-docs are being generated. However, trouble starts when rdoc should be created, the maglev provided gem command gives me

 gem install prawn
[INFO] The MagLev team publishes customized versions of some gems.
...
Successfully installed prawn-0.12.0
1 gem installed
Installing ri documentation for prawn-0.12.0...


RDoc failure in lib/prawn/images/jpg.rb at or around line 20 column 26

Before reporting this, could you check that the file
you're documenting compiles cleanly--RDoc is not a
full Ruby parser, and gets confused easily if fed
invalid programs.

The internal error was:

ERROR:  While generating documentation for prawn-0.12.0
... MESSAGE:   global $@ is a read-only variable
... RDOC args: --ri --op /Users/patru/.rvm/gems/maglev-head@invoice/doc/prawn-0.12.0/ri --title Prawn Documentation --main README -q lib README.md LICENSE COPYING GPLv2 GPLv3 --title prawn-0.12.0 Documentation --quiet
a RubySystemExit occurred (error 2752)

No big deal to live without documentation, it is good enough, but something else seems to go wrong, gem list says

Ascii85 (1.0.1)
bundler (1.0.21)
erector (0.8.3)
pdf-reader (0.10.1)
polyglot (0.3.3)
prawn (0.12.0)
rake (0.9.2)
treetop (1.4.10)
ttfunk (1.0.3)

so all seems to be well, but if I do

require 'ruby gems'
require 'prawn'

in irb (which works perfectly on my ree-1.8.7) I get a strange

NoMethodError: NoMethodError: undefined method `ruby_18' for 
from /Users/patru/.rvm/gems/maglev-head@invoice/gems/prawn-0.12.0/lib/prawn/core/object_store.rb:246:in `__compileClass'
from /Users/patru/.rvm/gems/maglev-head@invoice/gems/prawn-0.12.0/lib/prawn/core/object_store.rb:14:in `__compileClass'
from /Users/patru/.rvm/gems/maglev-head@invoice/gems/prawn-0.12.0/lib/prawn/core/object_store.rb:13:in `__compileClass'
from /Users/patru/.rvm/gems/maglev-head@invoice/gems/prawn-0.12.0/lib/prawn/core/object_store.rb:12
from /Users/patru/.rvm/rubies/maglev-head/src/kernel/bootstrap/Kernel.rb:831:in `gem_original_require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:57:in `require'
from /Users/patru/.rvm/gems/maglev-head@invoice/gems/prawn-0.12.0/lib/prawn/core.rb:78
from /Users/patru/.rvm/rubies/maglev-head/src/kernel/bootstrap/Kernel.rb:831:in `gem_original_require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:57:in `require'
from /Users/patru/.rvm/gems/maglev-head@invoice/gems/prawn-0.12.0/lib/prawn.rb:11
from /Users/patru/.rvm/rubies/maglev-head/src/kernel/bootstrap/Kernel.rb:831:in `gem_original_require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:59:in `require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:57:in `require'
from /Users/patru/.rvm/rubies/maglev-head/src/kernel/bootstrap/Kernel.rb:831:in `gem_original_require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:57:in `require'
from (irb):5:in `__compileEval'
from (irb):7:in `__compileEval'
from /Users/patru/.rvm/rubies/maglev-head/src/kernel/bootstrap/Kernel.rb:394:in `eval'
from /Users/patru/.rvm/rubies/maglev-head/lib/ruby/1.8/irb.rb:159:in `eval_input'
...

I am probably missing something obvious here. Suffice it to say that the 'erector' gem I installed as well (see the gem list above) can be required without problems, so I do not do everything wrong ;-)

GemStone doesn't start, says "no space left"

I'm trying to start GemStone for MagLev. Here is an error that I get in a log:

GemStone could not create the semaphore array required for the cache.

Reason: GemStone could not retrieve the IPC identifier associated with the semaphore key -704540831. semget() error = errno=28,ENOSPC, There is no space left on the device (or, in fcntl(), there are no more record locks).

Full logs are available in a gist.

Does it really lack space? I have 7 GB available. Are there any other issues in my case?