From: Eric Hodel <drbrain@...7.net>
Date: 2007-05-31T12:45:02+09:00
Subject: Re: DRb and Thread safety

On May 30, 2007, at 19:29, Erwin Abbott wrote:

> I've been reading about DRb and one issue that I still have questions
> about is thread safety.  Every website I've come across uses very
> basic examples where the client never does anything that would modify
> the distributed object.
>
> For sake of discussion, let's say I'm writing an application that's
> some kind of database. Clients can add, delete, search, or modify
> records. How can this be written so clients can't step on each other,
> or block the whole database while perfoming and update on a single
> record? Having a mutex for every record doesn't seem very elegant.

Having your database be a Rinda::TupleSpace is one way around it.

> I'm also still getting aquainted with threads, and I want to be sure I
> have this right: each thread has it's own "local" variables, so if two
> threads have access to the same array and they both call array.max...
> any local vars used in the #max method won't be "stepped on" by the
> other thread. As long as #max doesn't change any variables outside its
> method scope, it will be thread safe?

Correct.