Jack Casey created CASSANDRA-16860:
--------------------------------------
Summary: Add Snapshot Expiry via TTL to NodeTool
Key: CASSANDRA-16860
URL: https://issues.apache.org/jira/browse/CASSANDRA-16860
Project: Cassandra
Issue Type: New Feature
Components: Tool/nodetool
Reporter: Jack Casey
Opening this issue in reference to [this WIP
PR|https://github.com/apache/cassandra/pull/1148]:
h1. Summary
This functionality allows users of Cassandra to remove snapshots ad-hoc, based
on a TTL. This is to address the problem of snapshots accumulating. For
example, an organization I work for aims to keep snapshots for 30 days, however
we don't have any way to easily clean them after those 30 days are up.
This is similar to the goals set in:
https://issues.apache.org/jira/browse/CASSANDRA-16451 however would be
available for Cassandra 3.x.
h1. Functionality
This adds a new command to NodeTool, called {{expiresnapshot}} with the
following options:
NAME
nodetool expiresnapshots - Removes snapshots that are older than a TTL
in days
SYNOPSIS
nodetool [(-h <host> | --host <host>)] [(-p <port> | --port <port>)]
[(-pw <password> | --password <password>)]
[(-pwf <passwordFilePath> | --password-file <passwordFilePath>)]
[(-u <username> | --username <username>)] expiresnapshots [--dry-run]
(-t <ttl> | --ttl <ttl>)
OPTIONS
--dry-run
Run without actually clearing snapshots
-h <host>, --host <host>
Node hostname or ip address
-p <port>, --port <port>
Remote jmx agent port number
-pw <password>, --password <password>
Remote jmx agent password
-pwf <passwordFilePath>, --password-file <passwordFilePath>
Path to the JMX password file
-t <ttl>, --ttl <ttl>
TTL (in days) to expire snapshots
-u <username>, --username <username>
Remote jmx agent username
The snapshot date is taken by converting the default snapshot name timestamps
(epoch time in miliseconds). For this reason, snapshot names that don't contain
a timestamp in this format will not be cleared.
h1. Example Use
This Cassandra environment has a number of snapshots, a few are recent, and a
few outdated:
root@cassandra001:/cassandra# nodetool listsnapshots
Snapshot Details:
Snapshot name Keyspace name Column family name True size Size on disk
1529173922063 users_keyspace users 362.03 KiB 362.89 KiB
1629173909461 users_keyspace users 362.03 KiB 362.89 KiB
1629173922063 users_keyspace users 362.03 KiB 362.89 KiB
1599173922063 users_keyspace users 362.03 KiB 362.89 KiB
1629173916816 users_keyspace users 362.03 KiB 362.89 KiB
Total TrueDiskSpaceUsed: 1.77 MiB
To validate the removal runs as expected, we can use the `--dry-run` option:
root@cassandra001:/cassandra# nodetool expiresnapshots --ttl 30 --dry-run
Starting simulated cleanup of snapshots older than 30 days
Clearing (dry run): 1529173922063
Clearing (dry run): 1599173922063
Cleared (dry run): 2 snapshots
Now that we are confident the correct snapshots will be removed, we can omit
the {{--dry-run}} flag:
root@cassandra001:/cassandra# nodetool expiresnapshots --ttl 30
Starting cleanup of snapshots older than 30 days
Clearing: 1529173922063
Clearing: 1599173922063
Cleared: 2 snapshots
To confirm our changes are successful, we list the snapshots that still remain:
root@cassandra001:/cassandra# nodetool listsnapshots
Snapshot Details:
Snapshot name Keyspace name Column family name True size Size on disk
1629173909461 users_keyspace users 362.03 KiB 362.89 KiB
1629173922063 users_keyspace users 362.03 KiB 362.89 KiB
1629173916816 users_keyspace users 362.03 KiB 362.89 KiB
Total TrueDiskSpaceUsed: 1.06 MiB
Next Steps
To be completed:
- Tests
- Documentation updates
I am a new to this repository, and am fuzzy on a few details even after reading
the contribution guide 😅 Any advice on the following would be greatly
appreciated!
- What branch would this type of change be merged into? Currently, I'm
targeting {{apache:trunk}} by default
- Is there a test strategy/pattern for this type of change? I was not able to
find any existing tests for similar {{nodetool}} commands
Thanks! 😄
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
