SteveJ-restore-test

Two new things appeared in my world recently: A friend showed me Google 'Jump Desktop' , connecting his iPad to his Desktop. [Apple have their own 'Remote Desktop' product which I haven't researched. Not sure if it works over the wider Internet as well.] Joe Wilcox's piece (Jan-2011) on Apple dumping desktops sometime (soon) as they become less relevant. Wilcox wonders what will happen to "Power Users" if Apple move on Desktops, as they've moved on from the rack-mount X-serve line. Customers needing servers now have the choice of a Mac Mini Server or a "Mac Pro" (tower). Can Apple afford to cut-adrift and ignore the needs of good folk who rely on their product for their business/livelihood, some of whom may have used Macs for 20+ years?? Would seem a Bad Idea to alienate such core and influential users. Clearly Apple look to the future, and like the floppy drive they expunged long ago in favour of Optical drives (now also obsolete), Des...

Researching the history of Disk Storage and RAID since Patterson et al's 1988 paper has given me some surprises. Strictly personal viewpoint, YMMV. Aerodynamic drag of (disk) platters is ∝ ω³ r⁵  (RPM^3 * radius^5) If you double the RPM of a drive, spindle drive power consumption is cubed. All that power is put into moving the air, which in a closed system, heats it. Ergo, 15K drives run hot! If you halve the size of a platter, spindle drive power consumption is reduced by the fifth-power. This is why 2½ inch drives use under 5W (and can be powered by USB bus). There's a 2003 paper by Gurumurthi on using this effect to dynamically vary drive RPM and save power. Same author in 2008 suggests disks benefit from 2 or 4 sets of heads/actuators. Either to increase streaming rate or seek time, or reduce RPM and maintain seek times. The Dynamic RPM paper to be the genesis of the current lines of "Green" drives. Western Digital quote RPM as "intellidrive", but class ...

This started with an aside in " Crypto ", Stephen Levy (2000), about Rivest's first attempt at creating an RSA Crypto chip failing because whilst the design worked perfectly on the simulator, it didn't work when fabricated. [p134] Alderman blames the failure on their overreliance on Carver Mead's publications... Carver Mead and Lynn Conway at CalTech revolutionised VLSI design and production around 1980, publishing "Introduction to VLSI System Design" and providing access to fabrication lines for students and academics. This has been widely written about: e.g. in "The Power of Modularity" , a short piece on the birth of the microchip from Longview Institute, and a 2007 Computerworld piece on the importance of Mead and Conway's work. David A. Patterson wrote of a further, related, effect in Scientific American , September 1995, p63, "Microprocessors in 2020" Every 18 months microprocessors double in speed. Within 25 years, one...