eG Monitoring
 

Measures reported by PgMissingIdxTest

While at one end indexes greatly enhance database performance, at the other they also add significant overhead to table change operations. Useless/unused indices can therefore be unnecessary resource hogs. Such indexes are typically not used by any regular query and may not enforce a constraint. However, these unneeded indexes cost you in several ways: they slow updates, inserts and deletes; they may keep HOT from updating the row in-place, requiring more VACUUMs; they take time to VACUUM; they add to query planning time; they take time to backup and restore. Administrators hence need to identify such indexes and eliminate them. The PgMissingIdxTest helps administrators achieve the same. This test reports the number and names of unused/useless indexes, and thus prompts administrators to remove them so as to save the server from unnecessary performance degradations.

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
Number_of_index Indicates the number of indexes that are currently unused/useless on the server. Number A high value of this measure is a cause for concern. Use the detailed diagnosis of this measure to identify the unused indexes and take measures to get rid of them.