HopsFS is storing really small file in the database, in tables backed by filesystem table spaces for increased performance.
First you will need to stop the NameNode to avoid possible corruption
sudo systemctl stop namenode. Next step is to increase the tablespace size of NDB. We need to identify the name of the tablespace, normally it should be
ts_1 but we can check with querying MySQL.
Run the MySQL client
/srv/hops/mysql-cluster/ndb/scripts/mysql-client.sh and execute
FILE_NAME AS File, FILE_TYPE AS Type,
TABLESPACE_NAME AS Tablespace, TABLE_NAME AS Name,
LOGFILE_GROUP_NAME AS 'File group',
FREE_EXTENTS AS Free, TOTAL_EXTENTS AS Total
Assuming the name of the table space is
ts_1, we will add a new Datafile to this tablespace - 1Gb size - by executing,
ALTER TABLESPACE ts_1 ADD DATAFILE 'ts_1_data_file_1.dat' INITIAL_SIZE = 1G ENGINE = NDBCLUSTER;
Then you can restart the NameNode -
systemctl restart namenode - and it should come back. It’s advised to restart all other services.