unifi-controller:/var/lib/unifi/db# du -sh *
4.0K    ace
65M     ace.0
129M    ace.1
257M    ace.2
513M    ace.3
16M     ace.ns
65M     ace_stat.0
128M    ace_stat.1
2.0G    ace_stat.10
2.0G    ace_stat.11
2.0G    ace_stat.12
2.0G    ace_stat.13
2.0G    ace_stat.14
2.0G    ace_stat.15
2.0G    ace_stat.16
2.0G    ace_stat.17
2.0G    ace_stat.18
2.0G    ace_stat.19
256M    ace_stat.2
2.0G    ace_stat.20
2.0G    ace_stat.21
2.0G    ace_stat.22
2.0G    ace_stat.23
2.0G    ace_stat.24
513M    ace_stat.3
1.1G    ace_stat.4
2.0G    ace_stat.5
2.0G    ace_stat.6
2.0G    ace_stat.7
2.0G    ace_stat.8
2.0G    ace_stat.9
16M     ace_stat.ns
3.1G    journal
64M     local.0
16M     local.ns
4.0K    mongod.lock
4.0K    _tmp
4.0K    version