[ugen bulk read ahead code] This code was written under my direction back in 2006 to support the specific use case of the USRP with GNU radio. The only reason it's needed is to get better pipelining to get closer to the max transfer speeds.
So: are you doing something where not using read-ahead can't keep up? it is reasonably likely that there are bugs in cases that aren't like the USRP. And likely that no one else has ever tried what you are doing. So you shouldn't conclude that you are misunderstanding. This situation feels a bit like pipelined ethernet output with a start routine. If you can figure out a patch, I'm happy to review it.
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