myservice is run using
upstart, it has a configuration file
/etc/init/myservice.conf and possibly a compatibility file
/etc/init.d/myservice, but the latter is not a directory. It is very nonstandard to have subdirectories under either
That said, it is a very bad idea to change files which are part of the distro, because your changes might get overridden by an upgrade. All distros have mechanisms to avoid that, but you can never be sure they will work. So don’t mess up with
/etc/logrotate.d/upstart or wherever the stanzas you quote are from. This means you cannot have your log file under
The easiest solution for you is to create a directory
/var/log/myservice/, edit the file
/etc/init/myservice.conf to instruct your service to log to
/var/log/myservice/myservice.log (this is the trickiest part, read below) and then create a file
/etc/logrotate.d/myservice with the stanzas you want.
Serverfault has some hints on how to instruct your daemon to log somewhere else (you usually divert logging from upstart to syslog, then tell syslog where to log). I cannot tell you more since I know nothing about your service.