Re: Suggestion: xtime as new inode attribute

[Simon Horman <horms@verge.net.au>]

On Wed, Dec 16, 2009 at 07:57:30PM +0100, Daniel Poelzleithner wrote:
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> Hi,
> 
> I would like to suggest a new attribute for inodes in linux filesystems
> to record the last execution time of files.
> 
> The problem:
> 
> If a linux installation gets older and older, more and more programs get
> installed over time. Mostly to just test them for a particular problem
> and often the deinstallation is forgotten. To find out which packages
> are not used for a long time is currently quite impossible. The user may
> use program X which will run but not depend on program Y as a subprocess
> for example.
> 
> The solution:
> 
> I suggest a new inode attribute called xtime, which is like atime, but
> will only be updated when a file is executed. This would allow tracking
> of unused binaries and could be used with some clever algorithms in the
> cleanup program to find unused packages for removal or other cleanup
> purposes.
> It would also add an additional information in forensic analysis of
> hacked systems btw.

Given the existence of noatime and other related mount options
designed to mitigate the performance penalty related to atime,
adding xtime doesn't strike me as a particularly good idea.
I suspect there are easier ways to track when executables are
executed.