Fastruby v0.0.6 (PoC) released

Fastruby is a gem which allows to execute ruby code faster than normal (about 20X of the MRI1.8), see this post for more info

Improved ruby support

In the first gem released version of fastruby (v0.0.1), the ruby support was very limited since that version was designed as a spike (e.g. it can't handle block calls, exceptions, break, etc...).
These ruby support improvements are based on frame structures used at runtime and some other tricks such non-local goto's to implement return, next, break; this make the generated code a bit more expensive but still 20X faster (instead of 100X of the first version)

Now (version 0.0.6) fastruby support a wide range of ruby constructions, such:

• Exceptions (begin, rescue, ensure, end)
• Classes and modules
• Constants, globals
• Flow control sentences if, unless, and case..when..end
• Literals
• Singleton methods (almost as slow as normal ruby)
• Ruby built-in goto's (break, return, next)
  

But for now, leaves out the following:

• Class variables (*)
  
• Methods with multiple number of arguments (*)
• Callcc (*)

* Issue created for task

Native object cache to reduce bootstrap overhead

Usually the execution of ruby code on fastruby implies parsing the code, translate to C, and build by compiling it using gcc .
Even small code snippets may take a few seconds, a lot of time comparing it with the execution of same code using MRI, which takes hundredths of a second and imagining what would happen with larger code...
The response to this issue is the implementation of the cache, transparent to the invoker. In the image, a script is executed by first time to show it takes 0,642 seconds, and when the same script is executed again, the same script takes 0,057 seconds. The script test.rb is a very simple test:

require "fastruby"

fastruby '

print "hello world\n"

'

The cache is located on $HOME/.fastruby and the cache feature can be deactivated by setting the environment variable FASTRUBY_NO_CACHE to 1 when execute a ruby script that uses fastruby.

Implementation details of cache

As the diagram shows (click to view the full resolution version)

Each code snippet has a SHA1 sum associated and each SHA1 has a collection of native libraries including both the main object and multiple built of the methods defined in that snippet.
The diagram is only a conceptual model and does not represent any entity in fastruby source code, the sha1 association is implemented using the filesystem by saving each object collection in a directory named as the hexadecimal sha1 of the corresponding code snippet (inspired by git internals :D )




Links

Fastruby github page: https://github.com/tario/fastruby
Previous post on fastruby: http://tario-project.blogspot.com/2011/07/fastruby-v001-poc-released.html