Hi Laurens, many thanks for yours considerations. 1) I don't have problems about latency but I can't halt all during the computation. I can defer the computation for minutes if I attach to data the timestamp related to when data arrives. 2) The "monster" machine that have to do all is an embedded pc based on 1000MHz AMD Geode NX1500 3) The long computation need only the data. In extremis I could write data on a file or DB and compute using another program. I bit better explanation of scenario: The radiomodem take "unexpected data" from a network of varius sensors. The sensors could be reachable or not. The only way to know when the sensor is reachable is to wait fo "unexpected data". If I need to send data to a specific sensor I have to do it immediatly after it send me "unexpected data", wait also 1 second could be sufficient to have the sensor no longer reachable. I can't send data to sensor and after do computation because meanwhile could arrive data from another sensor. Mainly it is the reason because I think to defer long computation to another thread..