From: Charles Oliver Nutter <charles.nutter@...>
Date: 2007-09-06T03:43:27+09:00
Subject: Re: Accessing ruby 1.9 interpreter from other threads

Nobuyoshi Nakada wrote:
> Hi,
> 
> At Wed, 29 Aug 2007 19:16:00 +0900,
> Charles Oliver Nutter wrote in [ruby-talk:266657]:
>> A similar mechanism is used in JRuby to "adopt" incoming Java threads as 
>> Ruby threads, allowing them to participate in thread events like kill 
>> and raise. But there's nothing explicit about it; threads that haven't 
>> been adopted are adopted automatically. Can't this be done automatically?
> 
> Does that "adopt" occur in any call to ruby?  Isn't it
> performance overhead?

Not really, if the thread hasn't been adopted it just constructs a new 
Ruby thread to wrap it and a "thread context" to govern frames, scopes, 
etc for Ruby execution. That's a one-time hit that only happens the 
first time a normal Java thread enters Ruby code. From then on it 
largely just looks like any other Ruby thread.

- Charlie