Re: Threads are processes that share more

[Larry McVoy <lm@bitmover.com>]

On Thu, Jun 21, 2001 at 01:10:31AM +0200, J . A . Magallon wrote:
> 
> On 20010621 Stephen Satchell wrote:
> >
> >By the way, I'm surprised no one has mentioned that a synonym for "thread" 
> >is "lightweight process".
> >
> 
> In linux. Perhaps this the fault.
> In IRIX, you have sprocs and threads. sprocs have independent pids and you
> can control what you share (mappings, fd table...). Threads group under
> same pid.

I think that's accurate.

> Linux chose the sproc way...

That's not accurate.  The Linux way is an infinitely nicer architecture.
For each thing that is shareable you have code like

	vm_fork(... flags)
	{
		if (flags & VM_SHARE) return;
		do the work to fork the data structure
	}

In other words, it's designed to be shared.  The IRIX stuff is disgusting,
you really don't want anything to do with sproc().    It _sounds_ like they
are the same but they aren't - for example, with sproc you get your very
own TLB miss handler.  Doesn't that sound special?
-- 
---
Larry McVoy            	 lm at bitmover.com           http://www.bitmover.com/lm