Thank you for your reply. I completely understand the meaning of
backlog. And I found in my program the backlog can be as high as 1000
but it does not increase continusely. Sometimes it will decrease to
about 200, and all can work well. When I try to set a small buffer
size, error will occur immediately. I wonder how to compute the max
value of backlog so that the buffer size is big enough but is not too
big. I would like to know the detailed ways to optimize the buffered
acquisition although it's not my subject. Can you give me some
suggestions?
On Tue, 10 Feb 2004 08:16:45 -0600 (CST), alberto wrote:
>Hi,
>in a circular buffered acquisition the scan backlog indicates the
>number of acquired data to be retrieved from the allocated buffer.
>If
the scan backlog overcomes the buffer size an error (code:-10846)is
>generated, this situation occurs when you are not reading fast enough
>from the buffer untill you fill it.
>Therefore you have to keep the scan backlog at a low and above all
>stable level.
>Maybe the question is: how do I know if my application will meet this
>stable condition?
>Just try it and indeed check the scan backlog: if it remains at 0 or
>at a low level and doesn't increase continously, the application is
>robust; otherwise it needs to be optimized.
>There are many different ways to optimize a buffered acquisition, but
>maybe it is not the subject of your question.
>Anyway, these are general informations for buffered acquisition; you
>can find more details in the LV Data Acquisition Basics Manual.
>Hope it helps,
>Alberto
