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Unread 21-01-2010, 14:10
TheDominis TheDominis is offline
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Re: Some Camera Benchmarks

Quote:
Originally Posted by Greg McKaskle View Post
My questions were intended to help debug why the numbers are so different.
Greg McKaskle
I appreciate the response, but I failed to see how

Quote:
Are all of the timings you show above measured sequentially in the same task/thread? If they are in multiple tasks, it is easy for the OS to swap and double count an operation. In more detail, the OS commonly swaps for I/O tasks where a buffer or service may be busy. So if you measure time A, start I/O A, then the OS swaps and you measure initial time B, start I/O B, and at some point measure final time B, then the OS swaps back to measure final time A. This overlap of I/O and overlap of the A and B time intervals is very misleading as the A time includes the B time. Especially when measuring times via deltas, this can lead you to draw incorrect conclusions.
any of these things would matter. Such as task swapping due the fact that the image receiver and sender are on separate threads by default. Also I wasn't doing anything but camera tasks. My infinite loop consisted of a one second wait.

Wouldn't all of these things be bottlenecks for the camera operation anyway?
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