performanceprofilerxperfsystem-profiler

What is Hard Faults in XPerf


I'm trying to profile a system with XPerf. And see that performance problems occurs when there is activity in HardFaults ! Hard faults graph

But what I cant figure out and find in google what are these Hard Faults that xperf shows. What are they related to? What do they indicate? Is there any universal remedy for such situations? Hard faults table


Solution

  • Indeed. "First of all, a "hard fault" was previously called a "page fault" in earlier versions of Windows. Perhaps page faults were more easily understood from the name, too. A hard fault happens when the address in memory of part of a program is no longer in main memory, but has been instead swapped out to the paging file, making the system go looking for it on the hard disk. When this happens a lot, it causes slowdowns and increased hard disk activity. When it happens an awful lot, the possibility of hard disk thrashing arises. That's when a program stops responding, but the hard drive continues to run for an extended period. This has historically been referred to as "getting into the page file."

    Here is the article. http://www.brighthub.com/computing/windows-platform/articles/52249.aspx

    But be carefull with following suggestions of this article, because it is not quite correct to do so: http://player.microsoftpdc.com/Session/1689962d-dea2-48bd-80d8-96e954fa5329 http://player.microsoftpdc.com/Session/1c97b279-d7e3-4a3e-9a76-0dac23dfddb5