From: Joel VanderWerf <vjoel@...>
Date: 2008-12-27T01:23:27+09:00
Subject: Re: Are all Ruby built-in objects thread safe?

Just Another Victim of the Ambient Morality wrote:
>     I don't think this is relevant.  Concurrency isn't about how many 
> processors you use.  Multitasking systems existed long before SMP hardware 
> existed.  Concurrency is about doing tasks concurrently.  If you have one 
> method running and it may be preempted by another method then they are 
> running concurrently.  If the two methods share data then they may corrupt 
> that data for each other.  This is true regardless of how these 
> concurrencies, or threads, are implemented.  It doesn't matter if they're 
> hardware supported system threads or if they're Ruby green threads...

Keep in mind though that on smp systems, most instructions are not 
atomic. On a single processor, they are.

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407