Run GraphDB as a Standalone Server¶

The default way of running GraphDB is as a standalone server. The server is platform-independent, and includes all recommended JVM (Java virtual machine) parameters for immediate use.

Note

Before downloading and running GraphDB, please make sure to have JDK (Java Development Kit) or JRE (Java Runtime Environment) installed.

Running GraphDB¶

1. Download your GraphDB distribution file and unzip it.

2. Start the GraphDB Server and Workbench interface by executing the graphdb startup script located in the $graphdb_home/bin folder: A message appears in the console telling you that GraphDB has been started in Workbench mode. To access the Workbench, open http://localhost:7200/ in your browser. Options¶ The startup script supports the following options: Option Description -d daemonize (run in background), not available on Windows -s run in server-only mode (no Workbench UI) -p pidfile write PID to pidfile -h --help print command line options -v print GraphDB version, then exit -Dprop set Java system property -Xprop set non-standard Java system property Note Run graphdb -s to start GraphDB in server-only mode without the web interface (no Workbench). A remote Workbench can still be attached to the instance. Configuring GraphDB¶ Paths and network settings¶ The configuration of all GraphDB directory paths and network settings is read from the conf/graphdb.properties file. It controls where to store the database data, log files, and internal data. To assign a new value, modify the file or override the setting by adding -D<property>=<new-value> as a parameter to the startup script. For example, to change the database port number: graphdb -Dgraphdb.connector.port=<your-port> The configuration properties can also be set in the environment variable GDB_JAVA_OPTS, using the same -D<property>=<new-value> syntax. Note The order of precedence for GraphDB configuration properties is as follows: command line supplied arguments > GDB_JAVA_OPTS > config file. The GraphDB home directory¶ The GraphDB home defines the root directory where GraphDB stores all of its data. The home can be set through the system or config file property graphdb.home. The default value for the GraphDB home directory depends on how you run GraphDB: • Running as a standalone server: the default is the same as the distribution directory. • All other types of installations: OS-dependent directory. • On Mac: ~/Library/Application Support/GraphDB. • On Windows: Users<username>AppDataRoamingGraphDB. • On Linux and other Unixes: ~/.graphdb. GraphDB does not store any files directly in the home directory, but uses several subdirectories for data or configuration. Java virtual machine settings¶ We strongly recommend setting explicit values for the Java heap space. You can control the heap size by supplying an explicit value to the startup script such as graphdb -Xms10g -Xmx10g or setting one of the following environment variables: • GDB_HEAP_SIZE: environment variable to set both the minimum and the maximum heap size (recommended); • GDB_MIN_MEM: environment variable to set only the minimum heap size; • GDB_MAX_MEM: environment variable to set only the maximum heap size. For more information on how to change the default Java settings, check the instructions in the $graphdb_home/bin/graphdb file.

Note

The order of precedence for JVM options is as follows: command line supplied arguments > GDB_JAVA_OPTS > GDB_HEAP_SIZE > GDB_MIN_MEM/GDB_MAX_MEM.

Tip

Every JDK package contains a default garbage collector (GC) that can potentially affect performance. We tested GraphDB’s performance against the LDBC benchmark with newer versions (i.e., JDK 11 or higher), observing a drop when using G1GC. Tests were also conducted with the Parallel Garbage Collector (ParallelGC), this time producing normal results, i.e., no performance drop.

This is why we recommend experimenting with garbage collectors if using JDK 11 or higher, so as to find the option that would provide you with an optimal configuration.

Stopping the database¶

To stop the database, find the GraphDB process identifier and send kill <process-id>. This sends a shutdown signal and the database stops. If the database is run in non-daemon mode, you can also send Ctrl+C interrupt to stop it.