Hi Jon, > Firstly please confirm you are using a kfifo buffer? No, I use sw-ring. > Swring is deprecated but will do precisely what you are seeing I think. It uses a half full watershead to decide to signal userspace. If you wait till the buffer is full, unless your sampling is very slow you will have data coming in before userspace has read the whole buffer out. Hence you will loose data. You are right. I saw exatly what you said. > Kfifo has a more conventional poll and will fire off userspace whenever any data is in the buffer. Hence kfifo will work for your usecase. I would like to have a fill level capable buffer again in the future as they are very useful in high speed uses where latency doesn't matter. Ok, I will change my sw-ring buffer to kfifo! Thanks, Denis -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html