From: Bulat Ziganshin <bulatz@...>
Date: 2002-10-03T16:51:46+09:00
Subject: Re: Please help, question regarding threads

Hello Andrew,

Thursday, October 03, 2002, 11:25:07 AM, you wrote:

AC> I am worried about scalability, does using class variables for storing the
AC> data prevent a copy from being produced (loaded) once in each thread? That 
AC> is if the data is stored in class variables within their respective 
AC> objects, is there only one copy in memory that is shared among the various 
AC> threads that are running?

yes. ruby threads are very simple and light. it is close to just
switching "program counter" between several locations and no more.
data can be made local to the thread only by calling method or creating
closure (standard ruby ways to make local data) and class data is common for all threads:

class A
  def A.set(x)
    @@x = x
  end
  def A.get
    @@x
  end
end

A.set(1)
p A.get
Thread.new { A.set(2) }.join
p A.get



-- 
Best regards,
 Bulat                            mailto:bulatz@integ.ru