Just as Microsoft has intended it to be the Windows 7 blog run by two key figures of the Windows 7 development team has become one of the central information for information about the upcoming Microsoft operating system. The regular posts give insight into the development process, the development team and decision process but fail to deliver new information about the operating system itself.

It could be seen as a clever ploy by Microsoft to keep the news hungry blogosphere and crowd at bay by taking control of the Windows 7 news flow. Today’s post over at the blog is entitled Windows 7 Approach to System Performance, a much smaller article than the previous ones. Steven Sinofsky is again explaining theoretical and practical concepts that played a role in the Windows 7 development without mentioning any system requirements of the upcoming Windows 7 system.

It is nevertheless a good read from an engineering standpoint. He lists some of the metrics that the Windows 7 team is tracking during development including memory usage, cpu utilization and boot / shutdown / resume / standby times. He mentions criteria that they apply at the end of the milestones before they go into beta which have to be met and that they won’t ship the product if those criteria are not met.

We have criteria that we apply at the end of our milestones and before we go to beta and we won’t ship without broadly meeting these criteria. Sometimes these criteria are micro-benchmarks (page faults, processor utilization, working set, gamer frame rates) and other times they are more scenario based and measure time to complete a task (clock time, mouse clicks). We do these measurements on a variety of hardware platforms (32-bit or 64-bit; 1, 2, 4GB of RAM; 5400 to 7200 RPM or solid-state disks; a variety of processors, etc.) Because of the inherent tradeoffs in some architectural approaches, we often introduce conditional code that depends on the type of hardware on which Windows is running.

He also mentions that some users, usually the technical inclined prefer choice and customization, that some users want more eye candy while others prefer to go back to a Windows 2000 like experience.

..there are limits to what we can provide and at the same time provide a reliable “platform” that customers and developers can count on and is robust and manageable for a broad set of customers. But of course within a known context (within your home or within a business running a known set of software) it will always be possible to take advantage of the customization and management tools Windows has to offer to tune the experience

In conclusion Steven manages to provide some insight into yet another area of development while at the same time failing to provide any factual information about Windows 7.

For the first time since its creation another member of the Windows 7 development team has taken the opportunity to write a post on the Engineering Windows 7 blog. Michael Fortin who leads the Fundamentals feature team that is part of the Core Operating System group wrote about Boot Performance in general and Microsoft’s efforts to decrease the boot time and increase boot performance on the Windows plattform in general.

Michael adds a few interesting information, albeit general in nature, about the efforts in the Windows 7 development process. He mentions improvements in prefetching,

In terms of reading files from the disk, Windows 7 has improvements in the “prefetching” logic and mechanisms. Prefetching was introduced way back in Windows XP. Since today’s disks have differing performance characteristics, the scheduling logic has undergone some changes to keep pace and stay efficient. As an example, we are evaluating the prefetcher on today’s solid state storage devices, going so far as to question if is required at all. Ultimately, analysis and performance metrics captured on an individual system will dynamically determine the extent to which we utilize the prefetcher.

device and driver initialization,

As noted above, device and driver initialization can be a significant contributor as well. In Windows 7, we’ve focused very hard on increasing parallelism of driver initialization. This increased parallelism decreases the likelihood that a few slower devices/drivers will impact the overall boot time.

reducing the number of system services and their impact on the system

As an example Windows 7 effort, we are working very hard on system services. We aim to dramatically reduce them in number, as well as reduce their CPU, disk and memory demands. Our perspective on this is simple; if a service is not absolutely required, it shouldn’t be starting and a trigger should exist to handle rare conditions so that the service operates only then.

as well as improved diagnostics that aim to help the user who is facing the problems of a slow booting computer. One interesting graph that Michael embedded in the article was the mean boot time of millions of user systems. A majority of systems boots between 20 and 60 seconds but there are some that take more than 600 seconds to boot.

To sum it up. Microsoft is trying hard to reduce system boot time by introducing a few measures that allow this. It would be interesting to know for how many Windows users system boot time was a issue from the beginning.