Vista SP1 Performance

Poor performance was one of the sins associated with Windows Vista RTM, especially in comparison to Windows XP throughout 2007.
In this context, the Service Pack 1 for the operating system was long overdue as Microsoft faced what it seemed to be an ever increasing wave of criticism because of the sluggish pace at which Vista performed common tasks through which XP seemed to breeze with no issues. This situation was remedied with the introduction of SP1, and now Windows Vista's performance is placed under the microscope by a panel of IT professionals and Microsoft employees in a Springboard Series Virtual Roundtable with Technical Fellow Mark Russinovich (transcript available for download here).
The conclusion of the Springboard Series Virtual Roundtable focused on Vista performance is that the advent of Service Pack 1 helped clear the operating system of the problems it had as a RTM version. At the same time, it wasn't just the service pack, as much as it was the ecosystem of hardware and software solutions built around the platform growing more mature. In this regard, the optimization of computers' BIOS and drivers has contributed to speeding up Windows Vista, according to Gabe Aul, a principal group program manager for Microsoft specializing in Windows performance.
“So the scenario is that if a critical driver to the boot process, boots their driver, is not self-signed, embedded signed, then the system has to check the catalog file to see if there is a signature there in order for it to allow to progress,” Aul stated. “What happens though is that on a lot of systems, especially if you have gone through multiple driver updates, catalog files can accumulate and, suddenly, during the boot process you are scanning through a number of catalog files while you are waiting for, in order for the system to continue to load. So, embedding signing the driver will skip that step and that can save a considerable amount of time. Five to ten seconds on boot depending on the number of drivers and catalog files that are on the system.”
Aul also indicated that Vista is in fact superior to CP when it comes down to launching applications. This is where Vista-exclusive technologies come in, with the focus on superfetch. Aul explained that on XP, the cold launch of applications involved accessing the disk for all the bits and hitting a bottleneck for performance. This is no longer valid in Windows Vista because of the caching performed by superfetch.
“Having that stuff cached by superfetch means that your cold launch time if you’ve never launched this app in this session but superfetch has cached the data that predicts what I need, then than warm launch, or that cold launch time will be very, very close to warm. And, so, you should see with Vista that the app launch times are much more consistent than they were with XP when it could be very fast or very slow,” Aul explained.
source: news.softpedia.com