Archive for February 4, 2007

Sunday, February 4, 2007

ReadyBoost

I don’t really follow the Windows world, but I happened to read Peter Lewis’s article in the print edition of Fortune, where he mentions a new feature of Windows Vista called ReadyBoost. If your PC doesn’t have very much RAM, plug in a USB flash drive, and your PC gets faster. That sounded odd, since flash memory—whether in an iPod, a camera, or a USB key—has always seemed slow to me. After reading more about ReadyBoost, it turns out that flash memory is slow at sustained transfers, but that its access time is about ten times that of a hard disk. After all, there’s no platter to rotate and no head to be out of position. Even an iPod shuffle is faster than a hard disk for random 4K reads.

Vista uses the flash memory as a cache for parts of the virtual memory swap file, and this is apparently a big win for small page-ins. It routes bulk page-ins to the hard disk, even if the pages are on the flash, because with large transfers the disk will be faster. Flash drives wear out after a comparatively small number of writes, so apparently there’s also some kind of lazy writeback from the hard disk to the flash, reducing the number of writes so that the flash’s life will be extended to 10 years. All in all, I think this is pretty clever. The funny part is that Windows uses different drivers to connect to Plays For Sure devices, so they can’t be used with ReadyBoost. If you want to use your MP3 player to speed up your PC, get an iPod.

Programmers Don’t Like to Code

Jonathan “Wolf” Rentzsch wrote an excellent rebuttal to Scott “Dreaming in Code” Rosenberg:

Programmers desire to rewrite because they know that after starting with a clean sheet of paper and building it all again, at the end they’ll understand the whole. Programmers write code to learn.…Bad source bases irritate programmers because it shakes their foundation of understanding necessary to solve the problem. I reject the explanation that programmers capriciously want to rewrite code for the fun of it.

Update: also check out the responses he got.

Why You Should Be Using Disambiguated URLs

Simon Willison:

Links to (and within) your site should never, ever end with index.php / index.html / default.aspx / any default directory index filename.

The whole point those defaults is that you can link to the containing directory to see their content, resulting in a shorter and prettier URL. If you’re linking to them directly you’re missing out on a golden opportunity to disambiguate your URLs.

Whither GCC Technologies?

Randy B. Singer notes that GCC’s gccprinters.com Web site is for sale. Are they out of business?