After upgrade to UIM 8.51 the USM takes longer than 15 minutes to load for the first time.

  In 8.5.1 we are making heavier use of the data in the CM_Configuration_item table so we will need to clear out the erroneous/bogus data. 

In order to find out ci_types in your environment you can run the following query:

select * from CM_CONFIGURATION_ITEM where ci_name like '%Monitoring Profile%'

for data from sqlserver probe profiles you will get ci_types 4.2 and 4.2.1 for example.

You can find which probe has created the particular items in CM_CONFIGURATION_ITEM table for specific ci_types wit the following queries:

select * from cm_configuration_item where ci_type = '<ci_type>'

select * from CM_CONFIGURATION_ITEM_Metric where ci_id = '<ci_id from above output>'

select * from S_QOS_DATA where ci_metric_id = '<ci_metric_id from above output>' 

find the probe in the probe column of the S_QOS_DATA output.

- Now, for each robot where the respective probe is located, use the probe utility and enable "Expert Mode" and run the _reset_device_id_and_restart callback, or manually clear the contents of the /Nimsoft/niscache folder on the robot and restart it. 

deactivate discovery_server
run the following SQL queries:

DELETE FROM CM_CONFIGURATION_ITEM WHERE CI_TYPE LIKE '<ci_type>%';
DELETE FROM CM_CONFIGURATION_ITEM WHERE CI_TYPE LIKE '<ci_type>%';

These deletes will take a fair amount of time (maybe 15-20 minutes).

once the delete finishes, activate discovery_server.

For the next 4 hours or so, you may notice that some metrics relating to related probes may not appear in USM while the discovery_server rebuilds the CM_CONFIGURATION_ITEM table, but most likely you will not notice much of anything because most of the CI's we're deleting are "bogus" and have no corresponding metric to display. 

https://www.ca.com/us/services-support/ca-support/ca-support-online/knowledge-base-articles.TEC1160815.html