Threading (was: [OT] - REALBasic Claims 100K Users)

[Dar Scott]

On Oct 4, 2006, at 6:35 PM, Richard Gaskin wrote:

>> Well, one thing that leaps to mind immediately - stopping the  
>> entire  application freezing up when executing a lengthy shell  
>> script or  AppleScript.
>
> The operating system is already threaded.  This example doesn't  
> necessarily require Rev to give us the overhead and complexity of  
> running our own threads, merely to get notification of the  
> completion of an OS thread.

This is a good point.  This kind of thing can also improve efficiency  
even on single processor computers.  On computers with multiple  
processors, the improvement might be even better.

This can also apply invisibly within Revolution.  With multiple  
processors becoming popular, Rev might take care of some chores while  
waiting for I/O.  That is, even if a script blocks, Rev doesn't have  
to.  It might have some garbage collection, event preprocessing, or  
whatever to do.

This trend might make it worthwhile for Rev to move some chores to  
separate threads.

To some extent, applications that do file I/O and network I/O can  
shift some work to another processor just by giving the task to the  
system.  This shift is not as much as I expected, perhaps because the  
system is very efficient.  However, a db might be a task with enough  
work for one to see the work shifted to another processor.  I image  
some know how to reserve a processor.

A couple of my externals actually ran separate processes and  
communicated with those.  In those particular cases, that was not for  
efficiency reasons, though.

A very advanced Revolution compiler might shuffle code around so some  
work is done while "waiting" for a blocking operation.  There might  
be some clever look ahead or run ahead operations that can be done so  
things look faster.

Many apps made with Rev are part of a tool set in which several are  
used along with others.  These exploit all processors (normally).

So, I would expect that the IDE and apps can get much of the benefit  
of multiple processors and threading without threading actually being  
a part of the Revolution (Transcript) language.

Dar