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USB missed data issue.


Hi all,

This is my first post to this list (perhaps I should not admit that). We have a usb device that streams in data from a collection device. The problem we are experiencing is that occasionally (during very, very high machine load), we notice that some data is missed. After searching through the archives of this list, I found a few suggestions. The first was that I just load up the bus with read requests so that if my app. is not scheduled for a while, there will be some reads there to handle the data. The second was that we modify our app. to be able to handle lost data.

I have done both of these things. The first solution did indeed reduce the lost data samples by about 95%. So our actual loss rate is now well below 1% during extremely high load, and 0% during low load. As to the second solution ... well it does not crash anymore! :-)

The question I have is the following. Is this the ONLY thing I can do? I read that there was pretty much no way of ensuring a higher priority for handling usb reads even if I were to lug the whole thing into kernel land. Is this true? Or is there some really nasty "I don't care about anyone else" option?

Thanks,

Robert.


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