Hi Luke:
I reviewed this issue. Some comments
1) Typically restarting the TCS EM or updating the last_aggregated row in the TIM Collector (As said in the KD) value fixes it. See Knowledge Base Articles
2) You did not say what release you have. This issue should be fixed in 9.5.3, 9.6 and latter.
3) This is the type of issue which is quickest solved by opening a case and doing a webex. What would be looked at
- EM Health and activity (Logs, perflogs,supportability metrics)
- Tim Collector Log Review
- Database review of current partitions and contents. See when it last worked to determine what to set the LAR to.
That is hard to do over a community post but we will do what we can.
If you decide to open a case, let us know and the thread will be marked as answered. However, you are always wellcome to continue posting questions.
If you wish to continue working the issue though the community just a little longer, then follow the steps in TEC1309463, do an EM restart and report back.
Thanks
Hal German
APM Support