As an aside, my present problem really seems to be fixed -- I am able to move files of more than 2MB from one process to another within my Haskell program. In my program, I take the input file, turn it into a ByteString, pass it to process one, capture the result as a ByteString, pass it to process two, caputre that result as a ByteString and then put the ByteString into a file. Of course we'll see whether it really works in the next few days here -- but after I got the forking right I really there's little else to be done. However, it's clear this has been a problem in the past. Even if we just use this thread to collect "incidents" -- less specific than bugs, but more precise than simple suggestions of inadequacy -- it would help everyone to know what the limits are with the present runtime. -- _jsn