1 Introduction Tracker is a powerful desktop-neutral first class object database, tag/metadata database, search tool and indexer. Tracker is also extremely fast and very memory-efficient when compared with some other competing frameworks and has by far the fastest and most memory-efficient Nautilus search and Deskbar backends currently available. It consists of a common object database that allows entities to have an almost infinte number of properties, metadata (both embedded/harvested as well as user definable), a comprehensive database of keywords/tags and links to other entities. It provides additional features for file-based objects including context linking and audit trails for a file object. It has the ability to index, store, harvest metadata, retrieve and search all types of files and other first class objects. Supported first class objects include: * Files, Documents, Music, Images, Videos, Applications, Emails, Conversations, Playlists Planned support: * Appointments, Contacts, Projects, Tasks, Bookmarks, Notes, Firefox Web History All discussion related to tracker happens on the Tracker mailing list http://mail.gnome.org/mailman/listinfo/tracker-list IRC channel #tracker on: irc.gimp.net Bugs should be filed at: http://bugzilla.gnome.org. More infomation on Tracker can be found at http://tracker-project.org. Repository (first is readonly, second is write access) git://git.gnome.org/tracker ssh://@git.gnome.org/git/tracker 2 Use Cases Tracker is the most powerful open source metadata database and indexer framework currently available and because it is built around a combination indexer and sql database and not a dedicated indexer, it has much more powerful use cases: * Provide search and indexing facilities similiar to those on other systems (Windows Vista and Mac OS X). * Common database storage for all first class objects (e.g. a common music/photo/contacts/email/bookmarks/history database) complete with additional metadata and tags/keywords. * Comprehensive one stop solution for all applications needing an object database, powerful search (via RDF Query), first class methods, related metadata and user-definable metadata/tags. * Can provide a full semantic desktop with metadata everywhere. * Can provide powerful criteria-based searching suitable for creating smart file dialogs and vfolder systems. * Can provide a more intelligent desktop using statistical metadata. 3 Features * Desktop-neutral design (it's a freedesktop product built around other freedesktop technologies like D-Bus and XDGMime but contains no GNOME-specific dependencies besides GLib). * Very memory efficient. Unlike some other indexers, Tracker is designed and built to run well on mobile and desktop systems with lower memory (256MB or less). * Non-bloated and written in C for maximum efficiency. * Small size and minimal dependencies makes it easy to bundle into various distros, including live cds. * Provides option to disable indexing when running on battery. * Provides option to index removable devices. * Implements the freedesktop specification for metadata (http://freedesktop.org/wiki/Standards/shared-filemetadata-spec). * Extracts embedded File, Image, Document and Audio type metadata from files. * Supports the WC3's RDF Query syntax for querying metadata * Provides support for both free text search (like Beagle/Google) as well as structured searches using RDF Query. * Responds in real time to file system changes to keep its metadata database up to date and in sync. * Fully extensible with custom metadata - you can store, retrieve, register and search via RDF Query all your own custom metadata. * Can extract a file's contents as plain text and index them. * Can provide thumbnailing on the fly. * It auto-pauses indexing when running low on diskspace. 4 Compilation To compile and install Tracker, use the following commands : ./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var make sudo make install If you install using any other prefix, you might have problems with files not being installed correctly. (You may need to copy and amend the dbus service file to the correct directory and/or might need to update ld_conf if you install into non-standard directories.) 4.1 Notes on Solaris To compile Tracker with GCC on Solaris uses the following commands : CFLAGS="-D_POSIX_PTHREAD_SEMANTICS" ./configure \ --prefix=/usr \ --sysconfdir=/etc \ --localstatedir=/var \ --with-pic make sudo make install To compile Tracker with SUN Studio on Solaris uses the following commands, because there are some problems to compile exiv2 using SUN C++ compiler : CFLAGS="-D_POSIX_PTHREAD_SEMANTICS" ./configure \ --prefix=/usr \ --sysconfdir=/etc \ --localstatedir=/var \ --with-pic \ --disable-exiv2 make sudo make install 4.2 Compile Options Tracker has several compiler options to enable/disable certain features. You can get a full listing by running ./configure --help 5 Running Tracker 5.1 Usage Tracker normally starts itself when users log in. You can indexing by running: $prefix/libexec/tracker-miner-fs You can configure how this works using: $prefix/bin/tracker-preferences You can monitor data miners using: $prefix/bin/tracker-status-icon You can do simple searching using an applet: $prefix/libexec/tracker-search-bar You can do more extensive searching using: $prefix/bin/tracker-search-tool 5.2 Setting Inotify Watch Limit When watching large numbers of folders, its possible to exceed the default number of inotify watches. In order to get real time updates when this value is exceeded it is necessary to increase the number of allowed watches. This can be done as follows: 1. Add this line to /etc/sysctl.conf: "fs.inotify.max_user_watches = (number of folders to be watched; default used to be 8192 and now is 524288)" 2. Reboot the system OR (on a Debian-like system) run "sudo /etc/init.d/procps restart" 6 Further Help 6.1 Man pages Every config file and every binary has a man page. If you start with tracker-store, you should be able to find out about most other commands the SEE ALSO section. 6.2 Utilities There are a range of tracker utilities that help you query for data.