Re: announce: readahead-1.4

[Karel Zak <kzak redhat com>]

On Thu, Mar 01, 2007 at 02:40:08PM -0500, Dave Jones wrote:
> On Thu, Mar 01, 2007 at 11:50:26AM +0100, Karel Zak wrote:
>  > 
>  >  I have just pushed out a new 1.4 version of the readahead util.
>  >  The changes are:
>  > 
>  >     * move project to hosted.fedoraproject.org
>  >     * source code maintained by GIT
>  >     * various cleanups
>  >     * new build-system based on autotools
>  >     * --sort / --dont-sort support
>  >     * add readahead-collector (based on audit system,
>  >       requires audit-libs[-devel])
>  >     * improve init scripts (supports full, custom and fast mode)
>  >     * add /etc/cron.daily/readahead.cron (with readahead --sort)
>  > 
>  >  Web page:
>  > 
>  >     https://hosted.fedoraproject.org/projects/readahead
>  > 
>  > 
>  >  The code is not tested with FC7, because libauparse (from
>  >  audit-libs-devel) is broken in FC7 now.
>  > 
>  >  If you want to generate your customized version of readahead lists
>  >  you need to boot with "init=/sbin/readahead-collector". Also see
>  >  /etc/readahead.conf and /usr/share/doc/readahead-1.4/README*.
> 
> Out of curiousity, how much overhead would it add to always run
> the collector without needing any boot arguments?

 I don't have any numbers (yet), but I expect that audit rules for all
 open(), stat(), ... have a negative performance impact for kernel.

 (Well, Steve Grubb added to CC:-)

 The second problem is that auditd removes all rules during start up.
 It doesn't assume that there is any other tool that use kernel audit
 system :-)   (you need "chkconfig auditd off" now)

 I think for FC7 it's fine keep it for advanced uses only. I hope we will
 found a way how integrate the collector to distro. Maybe we will see
 better solution based on kernel -- for example fcache.

    Karel

-- 
 Karel Zak  <kzak redhat com>