A significant drop in performance may be seen when re-indexing a Solr core where deleted records (tombstones) are present, after upgrading to DSE5.1.2 or later.
DSE 5.1.2 - 5.1.7 (For NRT indexing)
DSE 5.1.8 - 5.1.9 (For RT indexing)
If the user triggers a re-index of the Solr core using dsetool, the overall time to complete indexing may be observed to take longer than with previous releases. This also affects indexing via update handlers (i.e. autoSoftCommit).
The Solr Indexing process metrics can also be observed by checking the IndexPool mbean
An issue was identified where more rows than necessary were being submitted to the indexing queue in DSE Solr. This in turn affected the indexing throughput.
Internal Jira DSP-15653 covers this issue for NRT indexing
Internal Jira DSP-16038 covers this issue for RT indexing
Upgrade to DSE 5.1.8, 6.0.0 or later for NRT Indexing.
Upgrade to DSE 5.1.10, 6.0.1 or later for RT Indexing.