Data deletion logic doesn't work

[holmes07]

BUG REPORT

Describe the bug
1.I got log like this :Space left on device /data11/bookkeeper/ledgers/current : 159412490240, Used space fraction: 0.95951813 > threshold 0.95.
2. then i set the namespace ttl from 86400 to 900 seconds
conf after updated :
"message_ttl_in_seconds" : 900,
"subscription_expiration_time_minutes" : 0,
"retention_policies" : {
"retentionTimeInMinutes" : 10,
"retentionSizeInMB" : 100
}
3. but still no log below 20% can be compact.
Compaction: entry log usage buckets[10% 20% 30% 40% 50% 60% 70% 80% 90% 100%] = [0, 0, 0, 2, 6, 91, 124, 102, 115, 2888]

4.It seems that the deleted ledger is not passed to the entrylog or ttl does not delete the ledger。iguess, but i don't know why???
Screenshots

Additional context
bookeeper version 4.11.0
pulsar version 2.6.0

[sijie]

@holmes07 The minor compaction threshold is 20% (https://github.com/apache/pulsar/blob/master/conf/bookkeeper.conf#L477). It means that minor compaction only kicks in when the active data usage is below 20%. From your log, it seems that the data usage of active ledgers are still above 20%. You might need to check why those ledgers are still active.