If anyone cares, I hacked in a few changes into a version of syslogd that we were using on some of our Linux boxes which enables you to send a signal to the daemon to toggle fsync()ing after every call to syslog(). Basically, if you’re using Linux and have something that does a lot of writing to the disk via syslog, and you don’t want to have to kill it and aren’t scared of losing some data if the system crashes, then you can just kill -USR2 pid and it will toggle the fsyncing. Grab it here.