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Re: feedback from google


Hi,

On Fri, 2005-05-13 at 17:53, Chen, Brad wrote:

> He suggested a couple examples off the top 
> of his head of things we'd want to monitor that pushed 
> well above the 1KHz event frequency range:
> - context switches. Just moving the mouse around on 
> the desktop can generate context switches at over 2KHz. 

Another one --- IO.  You can achieve typically in excess of 100 IOs/sec
on most disks; and a big server may have dozens of disks.  And you
probably want several probes for each IO --- possibly one in the VFS,
one when the IO hits a driver, one on IO completion, etc.  You'll hit
1KHz *very* easily once you start down that path.

--Stephen



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