Sep 222010
 

I have been looking into a problem with my Macbook Pro for quite a while now – despite setting the preferred sleep mode with sudo pmset -a hibernatemode 1, the laptop refuses to go into hibernate mode. It doesn’t even go into hibernate mode when the battery runs down sufficiently that it should do.

This leads to a couple of problems :-

  1. On occasions, the battery runs down enough to loose all power meaning my laptop switches off, and all running programs are terminated.
  2. Also the laptop sometimes comes out of sleep mode in my backpack getting very hot in the process.

According to a comment on a blog posting, there may be an issue with Firefox preventing hibernation from working – why that should be, I haven’t the faintest idea. Despite seeming a touch unlikely, I gave it a go – quitting Firefox and then putting the laptop to sleep.

And it hibernates!

However it turns out that stopping Firefox doesn’t prevent my main machine from hibernating. After a long hunt and several experiments, it turns out that OSX will simply not hibernate to a disk that isn’t in the slot where the hard disk is. Or in other words, you cannot hibernate when your boot disk in an SSD in the ExpressCard slot.

Which strikes me as a bit … weird. I guess the fix for this would be a proper SSD in the hard disk slot and to move the hard disk elsewhere.

After having invested in an SSD and spent far too long forcing my tired old eyes to operate in my MBP, I can confirm that hibernation does work with any kind of disk in the right slot for the hard disk.

Jan 072007
 

I recently replaced an elderly SGI Octane2 workstation which had 2 CPUs (400MHz MIPS-based), 1.5Gbytes of memory, and 3 elderly SCSI disks with a nice new Sun Ultra40 … 2 AMD Opteron 248s, 2Gbytes memory, and 2 mirrored SATA drives. It is interesting to compare the difference between an old-fashioned workstation originally designed in the middle to late 1990s with a 21st century PC. Not that I’m going to produce hard numbers from useful benchmarks … that is just too much work, and in some ways it is the feel of the differences that are important.

Of course this is not really a fair comparison. Whilst the SGI Octane is now very elderly and due to SGI managerial incompetence has not kept pace with PC performance as it should have done, it is after all a machine that originally cost 10-20 times the cost of the PC I am comparing it to. In car terms, I’m comparing a 20-year old Mercedes with a new and cheap Ford. I should point out that much of the software I am using is very much the same on both machines … the Enlightenment window manager, Sylpheed Claws as the mail client, Firefox as the browser, LyX as the word processor, and a text terminal for much of the remainder.

The PC is considerably quicker than the SGI of course. The graphic user interface is a good deal snappier, and most of the applications offer very welcome improvements in performance. With the exception of GIMP however, none of this performance increase is really essential; my old SGI ran pretty much everything my PC does, fast enough to get the job done. GIMP performance is the reason I upgraded, and here the difference is quite dramatic … filters that previous required patience now run almost instantly; when you are repeatedly trying things out in GIMP on quite large images this performance increase makes some things feasible that simply were not before.

There is one area where the SGI does offer some advantage over the PC; something I was expecting. The PCs disks are overall somewhat faster the the disks in the SGI (and of course I don’t have to pay to mirror my disks!), but the SGI tends to work more smoothly under high load. I’ve noticed before with the ‘low end’ on disks in PCs, that if you start to drive your disks very hard, the computer will sometimes stutter. Essentially the SGI was slower, but smoother under high disk load than the PC.

If was not for the need to run GIMP extensively (and the appeal of more standard add-on hardware like USB hard disks), there is no reason why I could not continue with the SGI. The tendency we have in the computing arena of replacing computers every few years is not a healthy one.