Page faults

[cameronsto]

QCD is causing a consistent 6 Page Faults/sec on my machine while playing a song. If I open a menu, start/stop, or do anything else this number jumps to 70+/sec.

Any ideas on why this is happening?

Cameron

[Paul]

A page fault is not a 'fault' that a user needs to worry about. It's just a term that means data that QCD needs was not in memory and had to go to the hard disk to get it. You will always get page faults when playing because the audio file is on the harddisk.

[cameronsto]

A page fault is not a 'fault' that a user needs to worry about. It's just a term that means data that QCD needs was not in memory and had to go to the hard disk to get it. You will always get page faults when playing because the audio file is on the harddisk.

So the fault is just the program buffering the song file into memory?

cameron

p.s.
I'm aware of what a page fault is, but didn't know it applied to just accessing a file.

[nwegner]

p.s.
I'm aware of what a page fault is, but didn't know it applied to just accessing a file.

Look up memory-mapped files, because Windows NT uses these everywhere. Basically, the OS' VM allocates some space to hold a file, but doesn't put it in memory. When an application tries to read from a location in the file, a page fault occurs, the OS loads the page (usually with DMA or something non-cpu intensive that may or may not load into physical memory), then the program continues.