[Popcon-developers] status of executables?

Wed Mar 2 23:54:03 UTC 2011

Thank you for replying so quick.

Indeed, mounting with strictatime did yield the desired result. I can
see how some "false positives" *could* happen:

1) Opening a directory with a GUI file manager changes atime (to obtain
file types).
2) Executing `file` on a file. Same as above.
3) Doing a `grep foo *` within a directory opens the file.

In addition to the required mount option, do you consider these to be a
problem? Do you deal with these "false positives" or do you consider the
result an acceptable margin of error?

My interest comes from working on a similar project. I had the same
problems and came up with a complicated solution. However, if you
already solved the problem, then the only reason to continue working on
my project is it's not necessary to get atime to achieve the end-result.
Albeit, that in itself may not be enough to continue my project since
somebody wishing to use Popcon can simply enable the required mount
option (at some performance cost, I suppose).

With respect,
Jeff Wicks

-------- Original Message --------
Subject: Re: [Popcon-developers] status of executables?
From: Bill Allombert <Bill.Allombert at math.u-bordeaux1.fr>
Date: Wed, March 02, 2011 4:12 pm
To: popcon-developers at lists.alioth.debian.org
Cc: jeff at linuxwest.com

On Wed, Mar 02, 2011 at 03:14:11PM -0700, jeff at linuxwest.com wrote:
> <html><body><span style="font-family:Verdana; color:#000000; font-size:10pt;"><div>Greetings nobile Popcon group;</div><div><br></div><div>How does Popcon know which binary executables have been used? Is /usr/bin/stat (or equiviliant) the method Popcon uses to get access times?</div><div><br></div><div> Running a simple test executable on my system does not cause the executable's status to change (I am not using noatime either). Does it work for any of you? Or, do you use some other method which is effective? Suppose a I have a package which consists of one executable and I use it frequently, will Popcon notice it?<br></div><div><br></div><div><br></div><div>Most sincerely,</div><div>Jeff Wicks<br></div></span></body></html>

Hello Jeff,

popcon use the atime. Unfortunately with recent kernels, this only work
100%
correctly if the mount option strictatime is used. Otherwise the atime
is not
100% accurate (I think the kernel default to relatime)

Cheers,
-- 
Bill. <ballombe at debian.org>

Imagine a large red swirl here.