Re: [RFD] 'nice' attribute for executable files

Wiktor
2005-03-30T16:04:27Z

Bodo Eggert wrote:
> Wiktor <victorjan@poczta.onet.pl> wrote:
>>so i thought that it would be nice to add an attribute to file
>>(changable only for root) that would modify nice value of process when
>>it starts. if there is one byte free in ext2/3 file metadata, maybe it
>>could be used for that? i think that it woundn't be more dangerous than
>>setuid bit.
>
> I guess there should be a maximum renice value ulimit instead, which would
> allow running allmost any user task on a higher nice level, except the
> important stuff, with the additional benefit of being able to temporarily
> renice some tasks until the more important work is done.
>
> I remember something similar being discussed for realtime tasks, but I don't
> remember the outcome.

my xmms problem is unimportant here, i've posted this thread to propose
some new feature in filesystem, not to solve problem with multimedia player!

max renice ulimit is quite good idea, but it allows to change nice of
*any* process user has permissions to. it could be implemented also, but
the idea of 'nice' file attribute is to allow *only* some process be
run with lower nice. what's more, that nice would be *always* the same
(at process startup)!
example:
web server runs as user www. it spawns perl interpreter that root wants
to be run with lower nice, but he doesn't want to allow 'www' user to
renice *any* process (for eg. this user is shared with webmaster, and
webmaster is malicious person; i know, the webmaster could have another
accout, but maybe for some file-ownership reasons, root doesn't want to
create special account for him).
in this situation, setting nice-attribute for /usr/bin/perl solves the
problem. remember, that this feature would also provide an easy way to
increase nice level. it can be done with shell script, but setting nice
value in file attributes is cleaner and easier to manage.

could it be implemented in some near future? thx for replies.

--
wixor
May the Source be with you.