Nepomuk Desktop Search Configuration

Sebastian Trueg

Anne-Marie Mahfouf

Revision KDE 4.12 (2013-11-01)


This module allows to configure certain parts of the desktop search and the Nepomuk semantic desktop. More information about the Nepomuk semantic desktop can be found at the Nepomuk homepage.

Basic Settings

The basic settings tab allows to enable or disable the semantic desktop and desktop search systems.

There are three checkboxes:

  • Enable Nepomuk Semantic Desktop Enabling the Nepomuk semantic desktop means that the Nepomuk services are running. These services provide metadata/annotation storage (files can be tagged or rated in Dolphin for example) but also desktop search which can be used through the KDE runner or again Dolphin.

  • Enable Nepomuk File Indexer Enabling the nepomuk file indexer means that the file indexer service is started in addition to the standard services already running. The file indexer service will run through all files in the configured folders (see below) and extract metadata from them (such as title or artist on music files or even simple things like the creation date). This metadata is then exposed through the desktop search just like the manual annotations mentioned earlier.

  • Enable PIM Data Indexer This option has to be checked to allow full text search in KMail.

On the right of Enable Nepomuk Semantic Desktop you can click on Details... and a dialog will inform you on the status of the KDE metadata store: how many files are indexed and the size of the store.

Under the Enable Nepomuk File Indexer checkbox the current status of the file indexing service is shown. The service has four normal operation states:

  • File indexer is idle - The file indexer is currently not working and waiting for an event to trigger an update (an event can be a newly created file or a changed file or a timeout for the recurring full check)

  • Indexing files in folder foobar - The file indexer is currently running though all files in folder foobar and analyzes new or changed files.

  • Scanning for recent changes in files for desktop search - The file indexer is currently performing its recurring check for new files in all index folders. This check is intended to find files that were not caught through normal file system monitoring.

  • File indexer is suspended - The file indexer has been suspended, i.e. it is in a paused state. This can either be triggered by the user or due to low disk space or a laptop being in a power-saving state. In the two latter cases the indexer will resume once the reason for the suspension has been resolved.

Apart from the normal operation states the indexer service can have an erroneous state. There are two possibilities:

  • File indexing service failed to initialize, most likely due to an installation problem - This should rarely occur that means that a mandatory plugin could not be loaded. This can be due to an installation problem (missing dependency) or due to a faulty setup of the KDE plugin system.

  • Any other error means a communication problem with the service. These errors are produced by the D-Bus subsystem and need to be evaluated case by case.


This tab allows to select the files and folders that are to be analyzed by the file indexer explained above. By default Documents, Audio, Images and Videos are selected here.

Click the Customize Folders button to select and de-select folders that should be searched for files to be analyzed. By default the home folder and all subfolders are analyzed. By simply unchecking a folder it can be excluded. It is also possible to include a subfolder of an excluded one by checking it again. This allows a rather fine selection of the folders to be analyzed.

Clicking the Advanced button allows to define exclude filters using the mime type or the name of a file. The mime types and names of all files found in the configured folders will be matched against these filters. Only if none of them matches the file will be analyzed. This is very helpful to exclude log and backup files and the like.

Removable media handling: Nepomuk can index files on removable devices like USB keys or external hard-disks for fast desktop searches. By default no files are indexed. Here this behaviour can be changed to one of two options:

  • Index files on all removable devices - Files on removable media are indexed as soon as the medium is mounted. Caution: this does not include media which have been rejected via the second option

  • Ask individually when newly mounted - The user will be asked to decide if files on the newly mounted medium should be indexed or not. Once decided Nepomuk will not ask again.


On this tab you can decide to make a backup of all data that could not be restored otherwise. This includes manually created tags, ratings but also statistical data. No backup is done as default so you need to decide what you want to do. You have two possibilities: automatic backups and manual ones.

Automatic Backups

First choose the Backup Frequency: this is set to Disable Automatic Backups but you can choose Daily Backup or Weekly Backup. Then set the Backup Time: to anything convenient for you using the spinbox: you can set the hour and minutes and the day of the week for weekly backups. Finally you can set a limit for the number of backup files using Max Number of Backups:. This will ensure you do not waste disk space with the backup files and only the N last files will be kept, N being the number you set there, 10 as default.

Your automatic backups are saved locally in the following directory: $KDEHOME/share/apps/nepomuk/backupsync/backups/.


  • Manual Backup... You can also perform manual backups. Manual backups will be saved in your chosen location, as a file. Click on Manual Backup... and a wizard will guide you. You first need to point to the location of the backup file. Enter a full valid path in the field or use the file dialog to point to a file.


    You can create a new file in the folder of your choice and then point to this new file.

    Then click on the Next button and the dialog should report that the backup has been done.

  • Restore Backup... If you want to later restore your backup, use this button and follow the wizard. The backup will be merged into the local Nepomuk database.