[mythtv] clone_vm

[travis eddy]

aaaaa, thanks.

yes i know you can have a remote backend... for some reason i get crazy "i 
ran out of audio buffers :-(" errors when i run the front or backend on my 
other computer.

>From: Colin Cross <colin at colincross.com>
>To: Development of mythtv <mythtv-dev at mythtv.org>, boscotwo at hotmail.com
>Subject: Re: [mythtv] clone_vm
>Date: Mon, 06 Dec 2004 12:44:14 -0500
>
>travis eddy wrote:
>
>>all of the mythtv threads. every one is "locked" to the machine they are 
>>run on. ( the openmosix won't move them if they have clone_vm enabled)
>>
>>thanks
>>-travis
>
>As Issac has pointed out, you are missing the difference between threads 
>and processes.  A thread is similar to a process, but by definition threads 
>share their memory space with all other threads of the same process.  I 
>don't know anything about openmosix, but as far as I can tell, it can only 
>move processes, and even then, only processes that do not share memory 
>(i.e. without clone_vm).
>
>In MythTV, mythfrontend is a process.  mythbackend is a process.  All the 
>different things that happen inside each of them are threads.  You cannot 
>separate threads across multiple machines, because they share memory space. 
>  There is no way to remove the shared memory from the threads, the entire 
>design of thread locking and synchronization relies on shared memory.  
>Since your hardware requirements mean both the frontend and backend 
>_processes_ have to run on the same computer, you are out of luck.  
>Openmosix could move the frontend process or the backend process to another 
>computer if your hardware didn't require otherwise, but Myth already has 
>this functionality with remote backends.
>