I have Percona 5.5.25 server running with binlogging, no slaves, and a high change rate (~100GB binlogs/day, 1 to 6 GB/hour varying through the day).
The server is configured with expire_log_days=2 and max_binlog_size=1G.
I expected to see old binlogs be removed more or less in sync with new binlogs being created, but it seems the expiry happens only around four times a day, but not in strictly regular intervals. See the attached graph showing disk usage for the directory containing the binlogs.
Is this a bug or feature, or an artifact of something in my Mysql server that I fail to see? I see that I can work around this by implementing expiry through external cronbased purging, but it would be nice to keep the log handeling interal in Mysql.