memgraph/docs/user_technical/installation.md

Installation

Memgraph is a 64-bit Linux compatible database management system. Currently, the Memgraph binary is offered only as a Docker image based on Debian Stretch. Before proceeding with the installation, please install the Docker engine on the system. Instructions how to install Docker can be found on the official Docker website. Memgraph Docker image was built with Docker version 1.12 and should be compatible with all latter versions.

Docker Import

After a successful download the Memgraph Docker image can be imported into Docker:

docker load -i /path/to/memgraph-<version>-docker.tar.gz

Image Configuration & Running Memgraph

Memgraph can be started by executing:

docker run -it -p 7687:7687 memgraph:<version>

The -it option enables displaying Memgraph's logs inside the current shell. The -p option is used to specify the port on which Memgraph will listen for requests. Memgraph uses the Bolt protocol for network communication, which uses port 7687 by default. The <version> part are 3 numbers specifying the version, e.g. 1.2.3.

It is recommended to perform some additional Docker configuration. Memgraph is currently an in-memory database management system, but it periodically stores all data to the hard drive. These storages are referred to as snapshots and are used for recovering data in case of a restart.

When starting Memgraph, a folder for snapshots needs to be created and mounted on the host file system. This can be easily done using Docker's named volumes. For example:

# Run Memgraph.
docker run -p 7687:7687 -v mg_data:/var/lib/memgraph memgraph:<version>

The -v option will make a named volume directory called mg_data and Memgraph will store snapshots there. Named volumes are usually found in /var/lib/docker/volumes.

The same can be achieved for logs and configuration. All supported volumes which can be mounted are:

• /var/lib/memgraph, for storing snapshots;
• /var/log/memgraph, for storing logs and
• /etc/memgraph, for Memgraph configuration.

Another way to expose the configuration and data is to use a full path to some directory on the system. In such a case, the directory first needs to be created and allow docker image to write inside. For example, to create a snapshots volume in the current directory:

# Create the snapshots folder on the host.
mkdir -m 777 mg_data
# Docker expects full path to the created folder.
FULL_OUTPUT_PATH=$PWD/mg_data
# Run Memgraph.
docker run -p 7687:7687 -v ${FULL_OUTPUT_PATH}:/var/lib/memgraph memgraph:<version>

In this example, -v mounts a host folder $PWD/mg_data to a path inside the Docker container.

Other than setting the configuration, it is also recommended to run the Docker container in the background. This is achieved with -d option. In such a case, the name should be set for the running container, so that it can be easily found and shut down when needed. For example:

# Run Memgraph.
docker run -p 7687:7687 -d --name <memgraph_docker_container_name> memgraph:<version>

Memgraph Configuration Parameters

Memgraph can be configured with a number of command-line parameters. The parameters should be appended to the end of the docker run command in the --param-name=param-value format. Following is a list of available parameters:

Name	Type	Default	Description
--interface	string	"0.0.0.0"	Communication port on which to listen.
--port	integer	7687	Communication port on which to listen.
--num-workers	integer	CPU count1	Number of Memgraph worker threads.
--log-file	string	"memgraph.log"	Path to where the log should be stored.
--snapshot-cycle-sec	integer	300	Interval (seconds) between database snapshots. Value of -1 turns taking snapshots off.
--snapshot-max-retained	integer	3	Number of retained snapshots. Value -1 means without limit.
--snapshot-on-exit	bool	false	Make a snapshot when closing Memgraph.
--snapshot-recover-on-startup	bool	false	Recover the database on startup using the last stored snapshot.
--query-execution-time-sec	integer	180	Maximum allowed query execution time. Queries exceeding this limit will be aborted. Value of -1 means no limit.
--memory-warning-threshold	integer	1024	Memory warning threshold, in MB. If Memgraph detects there is less available RAM available it will log a warning. Set to 0 to disable.
--query-plan-cache	bool Cache generated query plans.
--query-plan-cache-ttl	int	60	Time to live for cached query plans, in seconds.
--query-cost-planner	bool	true	Use the cost-estimating query planner.

To find more about how to execute queries on Memgraph please proceed to Quick Start.

Cleanup

Status and Memgraph's logging messages can be checked with:

docker ps -a
docker logs -f <memgraph_docker_container_name>

Memgraph and its Docker container can be stopped with:

docker stop <memgraph_docker_container_name>

After the container has stopped, it can be removed by executing:

docker rm <memgraph_docker_container_name>

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1. Maximum number of concurrent executions on the current CPU. ↩︎