The Old New Thing

June 1, 2012 - The Old New Thing

The time I watched a total lunar eclipse from the top of a mountain

June 1, 2012 Jun 1, 2012 06/1/12
Raymond Chen
One of my colleagues loves doing outdoorsy things, and he also loves space and astronomy. Many years ago, he invited a small number of us on an outing that combined both of his interests: A hike up a mountain to view the total lunar eclipse. Since an eclipse does not wait until you're ready, it's kind of important to stay on schedule or you'...

How do I prefetch data into my memory-mapped file?

June 1, 2012 Jun 1, 2012 06/1/12
Raymond Chen
A customer created a memory mapping on a large file and found that when the memory manager wanted to page in data from that file, it did so in 32KB chunks. The customer wanted to know if there was a way to increase the chunk size for efficiency. The memory manager decides the chunk size for memory-mapped files, and the chunk size is currently...