Why are full text indexes so slow in SQL Server?

Why are full text indexes so slow in SQL Server?

The main cause for reduced full-text indexing performance is hardware-resource limits. CPU. If CPU usage by the filter daemon host process (fdhost.exe) or the SQL Server process (sqlservr.exe) is close to 100 percent, the CPU is the bottleneck.

Why does SQL Server use AWE memory for full text search?

Beginning in SQL Server 2008, the Full-Text Engine can use AWE memory because the Full-Text Engine is part of the sqlservr.exe process. For more information, see Full-Text Search architecture. If the system has no hardware bottlenecks, the indexing performance of full-text search mostly depends on the following:

When does error occur during a full text search?

When an error occurs during a crawl, the Full-Text Search crawl logging facility creates and maintains a crawl log, which is a plain text file. Each crawl log corresponds to a particular full-text catalog.

How to improve the performance of full text indexes?

When a population has completed, a final merge process is triggered that merges the index fragments together into one master full-text index. This results in improved query performance since only the master index needs to be queried rather than a number of index fragments, and better scoring statistics may be used for relevance ranking.

How can i Improve my SQL server indexing performance?

The primary workaround is to create full-text catalogs that are separate from the SQL Server database files and logs. Put the logs, database files, and full-text catalogs on separate disks. Installing faster disks and using RAID can also help improve indexing performance.

Where are full text indexes stored in SQL Server?

In a previous article entitled Hands on Full-Text Search in SQL Server, we had an overview on the Full-Text feature as it’s implemented in SQL Server. We saw how to create Full-Text indexes and that they were stored inside a container called a Full-Text catalog.

When to consider a full text index rebuild?

To sum up, here are the cases when a Full-Text index should be considered for rebuild: When its size is above 1Mb and has a fragmented space of 50Mb or more. This ends up the definition for thresholds to use for Full-Text index rebuild option. We can now consider Full-Text catalog reorganization.

How are full text indexes maintained in stack?

As it’s well explained by Geoff Patterson in his stack exchange ticket entitled “ Guidelines for full-text index maintenance ”, there are two possible ways to maintain Full-Text indexes: Using DROP/CREATE pattern (we’ll call it index rebuild): we first drop the index than create it again.