Subject: Re: Linux processes, tempfs and programs

From: Stephen Williams <[email-masked]>
Date: Thu, 17 Feb 2005 16:53:05 -0800

Eugene Surovegin wrote:
| On Thu, Feb 17, 2005 at 03:38:05PM -0800, Stephen Williams wrote:
|>But if I do that, I want to remove the program from the directory
|>after I start it, so that the file does not take up ram space. Will
|>that actually work? I'm using exec(2) to execute the program file
|>wherever it is downloaded. Will a subsequent unlink of the file
|>have a result, or will the file continue to take up space as
|>backing store for the executable?
|
|
| I think unlink will remove the file from directory (so you won't be
| able to see it with ls), but it will still continue to to take space -
| you're right it will be used as backing store, at least for read-only
| segments, which can be discarded if memory is tight. Even if you mlock
| all executable in memory, I think there will be still at least one
| reference to this file, which will prevent freeing tmpfs memory.

Which is what I thought, and why I didn't do it that way in the
first place:-( That's 128+ Kbytes I'd rather have holding image
data:-(((

I've got shared libraries on the CF disk, it's fine (preferable) if
it pages out of them, but I don't want the program itself to reside
anywhere but in its memory image. (And I don't want to go writing to
the CF disk except for upgrades or sys admin stuff.)
- --
Steve Williams                "The woods are lovely, dark and deep.
steve at icarus.com           But I have promises to keep,
http://www.icarus.com         and lines to code before I sleep,
http://www.picturel.com       And lines to code before I sleep."