John Markoff has an interesting piece in the New York Times about the frenzied efforts within Microsoft to get Vista ready to ship. The article has some interesting statistics. For example, it quotes the Gartner Group as claiming that Windows runs on 845 million computers worldwide and Office on more than 450 million.

Markoff claims that

it was the vast scale of the Windows testing program that saved the software development projects. Over the summer, the company began an extraordinary bug-tracking effort, abetted by volunteers and corporate partners who ran free copies of both Windows and Office designed to send data detailing each crash back to Microsoft computers.

The Office package, for example, has been tested by more than 3.5 million users; last month alone, more than 700,000 PC’s were running the software, generating more than 46 million separate work sessions. At Microsoft, 53,000 employee computers are running test versions.

Vista has also been tested extensively. More than half a million computer users have installed Vista test software, and 450,000 of the systems have sent crash data back to Microsoft.

One interesting question is how Microsoft manages to cope with the torrent of data that comes back from all these test versions. Markoff says that The test data from the second beta release of Vista alone generated 5.5 petabytes of information — “the equivalent of the storage capacity of 690,000 home PC’s”.

Later… James Miller points out that the last calculation — which is the work of the New York Times, not me — implies that the average home PC has a hard disk of 8GB capacity, which seems implausible. If we assume that the average PC now has 80GB of hard disk space, then 5.5 petabytes equates to 68,500 PCs. Looks like a decimal point went missing somewhere.