For the Java servers (Blitz-0.log.* and Indexer-0.log.*) the file sizes are defined in
log4j.xml.
For the Python servers, the files sizes are defined in
source (I've just added
ticket:1519 to make it configurable.)
For both, the default is to allow up to 9 backup files of up to 500MB for a total of 4 GB of log data. Once the log files have rolled over, however, it is completely safe to delete or compress them. We'll add documentation on this point with the 4.1 release (
ticket:1520)
Thanks for pointing it out!
~Josh.