On April 17, 2011 10:47:19 am Craig McLean wrote: > I've mostly figured it out > > Gustin's suggestion is something I've done in the past but in this case > there was no text box where I could enter an arbitrary string that I could > then grep for. What I finally did was use the find command to find all > files modified in the last 60 seconds. That technique found > > ~\.gconf\apps\gnome-power-manager/disks/%gconf.xml > > That technique of finding all files modified very recently didn't work > reliably. It looks like Gnome or some subset of it does not flush changes > made in the GUI to config files immediately, it can sometime take a few > minutes before they show up on the file system. So I only really > discovered the config file using this technique because I was lucky. > After Gustin mentioned gconf-editor I used that and found it in there as > well. > > All this really did was raise another question. I know what text file the > setting is maintained in, but that still doesn't answer how the setting > actually gets set on the system. Some more digging found that > gnome-power-manager uses dbus to communicate these settings changes to a > daemon called upower. It looks like upower manipulates the kernel > directly to do power management, however I haven't absolutely confirmed > this yet. > > It looks like hdparm and hdparm.conf aren't used under normal circumstances > on an Ubuntu 10.10 desktop. That is a little bit annoying because on a > standard Ubuntu 10.10 desktop the hdparm.conf file is sitting there in > /etc with no warnings about how you really shouldn't be using it to manage > power if you have Gnome installed. It looks like the hdparm.conf file > will still get used if you do set things in it, which I suspect could lead > to hilarious and infuriating problems for the unwary. > > If anybody knows if upower calls other tools or just manipulates the kernel > directly I'd be interested to know. > > > > -----Original Message----- > From: clug-talk-boun...@clug.ca [mailto:clug-talk-boun...@clug.ca] On > Behalf Of Gustin Johnson Sent: April-17-11 4:04 AM > To: CLUG General > Subject: Re: [clug-talk] Slightly Obscure Ubuntu Question > > My first guess is that it is something buried in gconf-editor (this is > like regedit for GNOME, a really bad IMO). Failing that, what I have > done is set some weird value, in this case a random 3 digit number, > and then gone grepping through the file system looking for that > number.
I was curious about that too so I looked on wikipedia and what happens is that there is a gconf-daemon that examines when a file in the ~/.gconf (and also /etc/gconf ?) directory is made. When it detects a change to one of the XML files (presumably its using inotify for that) then it changes the setting that is called for. I've never liked Gnome and I don't like this somehow. Sometimes when I don't like something like this its a day or two before I have my thoughts sorted out on the matter - we'll see. I can see what they were trying to do, ie. bring some sanity to the many many different config files from /etc that all have their own syntax. However, immediately what strikes me is that I hope they have taken care of the condition where the system is interrupted when making a change to one of these XML files that leaves the XML file syntactically incorrect (not to mention that I hate XML in the first place!!! My preference would be JSON). The way around this would be to create the XML file elsewhere then copy the file into place while ensuring that the file is smaller than one 4k block. _______________________________________________ clug-talk mailing list clug-talk@clug.ca http://clug.ca/mailman/listinfo/clug-talk_clug.ca Mailing List Guidelines (http://clug.ca/ml_guidelines.php) **Please remove these lines when replying
