How are you running postgres? If the logger process runs into trouble it might write to stderr.
Is there a chance your huge statements would make you run out of space?
Well, I don't think it is a out of space problem, because it doesn´t stop logging, it just splits that message. As you can see, the next message is logged properly. And that statement is not so huge, these statements have not more than 10 or 20kb. And as I said these statements occur dozens of times a day, but only once or twice is not correctly logged
An additional info, that splitted message has an out of order log time. At that time the log file was having 2 or 3 logsper second, and that message was 1 or 2 minutes later. It seems like it occurs now but it's stored a minute or two later.
