Correct Answer:
Explanation/Reference:
Note:
Resolution: Enable and run the crawl database defragmentation health rule
1. Verify that the user account that is performing this procedure is a member of the Farm Administrators group.
2. In Central Administration, on the home page, click Monitoring.
3. On the Monitoring page, in the Health Analyzer section, click Review rule definitions.
4. On the All Rules page, in the Performance section, click Search – One or more crawl databases may have fragmented indices.
5. If the rule is not enabled, in the Health Analyzer Rule Definitions dialog, click Edit Item on the ribbon. Ensure that the Enabledcheck box is selected, and then click Save on the ribbon.
6. On the ribbon, click Run Now.
7. Click Close.
The rule iterates over all crawl databases in all Search service applications. When it runs, it attempts to perform an online defragmentation first, and then it switches to offline defragmentation where required. In online defragmentation, only the SQL Server leaf pages are defragmented, not the SQL Server locked pages. In offline defragmentation, the locked pages and all the leaf pages are defragmented.
Reference: Search – One or more crawl databases may have fragmented indices (SharePoint 2013)
