What does nodetool cleanup do?

What does nodetool cleanup do?

Cleans up keyspaces and partition keys no longer belonging to a node.

When should I run Nodetool cleanup?

You should run nodetool cleanup whenever you scale-out (expand) your cluster, and new nodes are added to the same DC. The scale out process causes the token ring to get re-distributed. As a result, some of the nodes will have replicas for tokens that they are no longer responsible for (taking up disk space).

How do I clean my cassandra database?

1 Answer. Cassandra keeps deleted data as a safe guard whend dropping or truncating tables / keyspaces. nodetool clearsnapshot will remove those snapshots. After that I use a simple find /var/lib/cassandra/data**/ -type d -empty -print to clean things up.

What is Nodetool repair?

Repair – a process that runs in the background and synchronizes the data between nodes. When running nodetool repair on a single node, it acts as the repair master. Only the data contained in the master node and its replications will be repaired.

What does Nodetool compact do?

Forces a major compaction on one or more tables. Forces a major compaction on one or more tables.

How do I check Nodetool status?

nodetool status

1. Status – U (up) or D (down) Indicates whether the node is functioning or not.
2. State – N (normal), L (leaving), J (joining), M (moving), or S (stopped) The state of the node in relation to the cluster.
3. Address. The node’s URL.
4. Load – updates every 90 seconds.
5. Tokens.
6. Owns.
7. Host ID.
8. Rack.

What is cleanup in Cassandra?

Cassandra nodetool has a command called cleanup : cleanup [keyspace][cf_name] Triggers the immediate cleanup of keys no longer belonging to this node. This has roughly the same effect on a node that a major compaction does in terms of a temporary increase in disk space usage and an increase in disk I/O.

How do you clean Cassandra tombstones?

Procedure

1. Monitor the average transaction time to gauge how often to remove tombstones.
2. Stop each Cassandra node.
3. Edit the following settings in cassandra. yaml that affect tombstone removal and compaction: tombstone_threshold.
4. Run reaper and compaction processes.
5. Repeat steps for each node.
6. Restart each node.

How do I run Nodetool repair?

It is run by the operator via nodetool.

1. Incremental repair is the default and is run with the following command: nodetool repair.
2. A full repair can be run with the following command: nodetool repair –full.
3. Additionally, repair can be run on a single keyspace:
4. Or even on specific tables:

How do I check my cassandra compaction status?

If you grep the cassandra log file for lines containing Compacting you will find the sstables that are part of a compaction. If you sum these sizes and multiply by the inverse of your compression ratio for the column family you will get pretty close to the total.

How do I stop compaction in cassandra?

Procedure

1. Log in to the server where a Cassandra node is installed.
2. Go to /apache-cassandra/bin directory.
3. Type ./nodetool setcompactionthroughput 0. Tip: To run nodetool, JAVA_HOME must be set to the location of IBM JDK 8. Setting the value to 0 , disables compaction throttling.

What is own Nodetool status?

Nodetool status uses the Owns column to indicate the effective percentage of the token range owned by the nodes. Because different keyspaces have different replication strategies, nodetool is not able to calculate a meaningful ownership percentage.