On Wed, Nov 02, 2005 at 05:28:35PM -0600, Rob Landley wrote:
> With fragmentation reduction and prezeroing, UML suddenly gains the option of 
> calling madvise(DONT_NEED) on sufficiently large blocks as A) a fast way of 
> prezeroing, B) a way of giving memory back to the host OS when it's not in 
> use.

DONT_NEED is insufficient.  It doesn't discard the data in dirty
file-backed pages.

Badari Pulavarty has a test patch (google for madvise(MADV_REMOVE))
which does do the trick, and I have a UML patch which adds memory
hotplug.  This combination does free memory back to the host.

                                Jeff


-------------------------------------------------------
SF.Net email is sponsored by:
Tame your development challenges with Apache's Geronimo App Server. Download
it for free - -and be entered to win a 42" plasma tv or your very own
Sony(tm)PSP.  Click here to play: http://sourceforge.net/geronimo.php
_______________________________________________
User-mode-linux-devel mailing list
User-mode-linux-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel

Reply via email to