I've seen it said to "NEVER" apply auto_explain's log_analyze parameter on Production. I get the general foreboding doom that can be beset by a highly looping control structure eating up disk space (with no indication of its exit condition time) but is genrous-disk-writes pretty much the only reason for avoiding this in folk's opinion?
log_analyze doesn't take up dreadful amounts of disk space. log_min_duration and sample_rate are how you control disk usage.
Some systems (combination of hardware and kernel) have slow clock access, and turning on log_anayze will greatly slow down your CPU-bound queries on such systems (I've seen as much as 10x slower), even the queries that end up not meeting log_min_duration. If you are running a modern kernel on modern hardware, that probably isn't a problem. It will still down queries by some amount, but probably not enough to matter, assuming the information it produces is valuable to you.
