Posts tagged ‘MacOSX’

I just read an interesting article on how HFS+ deals with fragmentation. Not only will it take proactive steps to avoid fragmentation, apparently it will defragment some files on-the-fly.

This forensics-site has a very detailed article on the hex-dumps you can get from an HFS+ partition.

I’m again having problems with my new MacBook Pro (the late 2008 unibody one). The problem is most easily visible when BootCamping into Windows and running whatever 3D application (I use 3DMark06). Within 5 minutes, the machine crashes. After some trail-and-error, I found out that it appears to be a thermal problem.

Normally, when the load goes up, the fans kick in to keep the temperature down. Mine don’t… When stressing my CPU under MacOS, it happily goes up to 90ºC with the fans still idling at their standard 2000rpm. Needless to say, a bit of GPU-load increases the temperature beyond the safety-thresholds.

Resetting the SMC solves this problem only partially. On the first boot with a clean SMC, the same CPU-test brings the CPU to 70ºC with fans blazing at 4750rpm, as it should be. Once the machine goes through a sleep-wake cycle, the same test brings it straight up to 90ºC.

Just when I was about to call Apple Care, a software update pops in: SMC Firmware Update 1.2, looked promising, but the problem persisted… I’ll call Apple Care tomorrow.

Continue reading ‘Cooling problem with MacBook Pro’ »

Since PhotoShop is a bit too expensive, I’m sticking to The GIMP. When trying to get The GIMP to work under MacOSX (Leopard) I had two issues. The first one was a huge lag in the mouse pointer. Apparently this was caused by a specific version of X11. Since I’ve updated to 10.5.6, the problem disapeared by itself.

A second issue I was having is that (by default) the first mouse-click simply activates the window. The GIMP uses multiple windows, making this very anoying: to switch to another tool, I had to click twice. This blogpost gives the solution:

$ defaults write org.x.X11 wm_click_through -bool true

In my home setup, the Wireless LAN and the Wired LAN are on different subnets. The communication between the two is fully routed, so from the IP point of view, this works perfectly. Most protocols just use DNS and just work. There are, off course, some exceptions to this rule that needs special treatment. One example is, big surprise, Microsoft’s name resolution which works by using broadcasts. Since routers don’t forward broadcasts, you need a trick to get this to work across subnet boundaries: a WINS server.

Another example is Apple’s Bonjour protocol (aka Zeroconf aka Avahi aka Rendezvous). The technical details are a bit different (multicasted instead of broadcasted; based on DNS instead of proprietary protocols), but the result is the same: it doesn’t work across subnet boundaries. Obviously, this protocol is extended to work over a Wide Area Network (WAN), but for some reason, Apple decided that iTunes (and iChat) only supports local Bonjour. (It won’t surprise me if the RIAA has something to do with this.)

Continue reading ‘Sharing iTunes across subnet boundaries’ »

My car has a CD player build-in that supports MP3 CDs. However, it’s fairly picky on the format of the disc. I tried to burn a CD using Burn Folder which comes with Leopard, which creates a multistandard disc containing a HFS+, an ISO-9660 with Rock Ridge, and a Joliet with Rock Ridge. While this looks very nice on paper, the car’s CD player was less satisfied: “Error CD”.

Another issue is that the player has no support for M3U-playlists. It does, however, support “albums” (directories), which can be used to emulate playlists. Just add a number prefix to each filename and it’ll work. Placing the same file in multiple playlists/albums/directories is possible, but wastes space. But this can be worked around.

Continue reading ‘Faking playlists on an MP3 CD’ »

Time Machine is the Mac way of doing backups. The concept is fairly similar to incremental rsync snapshots. Officially, Apple does not support Time Machine backups to a network volume: network drives don’t show up in the Time Machine user interface. The only way to get network-based Time Machine is by buying a Time Capsule.

When doing a Time Machine backup to a normal disk (I tried it with a LaCie 1TB USB disk), one can see the file structure created. Mine looked like this: Backups.backupdb///Macintosh HD/… Inside this directory is my full system (minus the parts I explicitly excluded in the Time Machine config).

Since we have more than 1 Mac, I’d like to have all of them back up to the same hard drive. I already have a Linux-based server serving files over AFP. This is where it gets more interesting…

Continue reading ‘Time Machine to a linux server’ »

I’m a bit paranoid when it comes to security. For example, I don’t allow passwords to log into my computers via SSH but use RSA keys instead. Besides added security (there is no password to guess), it has a lot of other advantages as well. I normally run an ssh-agent (both on linux and Windows) which caches my credentials so I can log in without password.

On my desktop system, this was automatically secure against theft. Since the key is stored in RAM (or encrypted swap), it is flushed the moment the computer looses power. Since it was a desktop system, it’s fairly safe to assume that the power will be cut when someone steels my computer.

On my new MacBook Pro, things are a bit different: most of the time, my notebook is in standby and has an integrated UPS (its battery). So I was looking for something to get me the same security.

Continue reading ‘Securing SSH Agent on Mac OS X’ »

I just came across some very weird behavior on a family members Apple MacBook. For whatever reason, Finder does NOT show all files in a folder. The folder is located on an SMB share, but I’m not sure if this has anything to do with it. The machine is fully patched with all software updates available on the day of this post.

Here is a screenshot illustrating the behaviour (some text blurred intentionally to protect privacy):

As you can see, the Terminal DOES show all files (e.g. the “untitled folder”).

Until here, this seems strange, but is probably some weird setting somewhere. But it gets a lot weirder.

Continue reading ‘Weird MacOS X Leopard behaviour: Finder hides files’ »