rcm.cr

Redis Cluster Manager in Crystal

• in beta stage (crystal-0.18.2)

Usage (information features)

nodes

• provides human-friendly output rather than redis-cli

% rcm -p 7001 nodes
89580c [127.0.0.1:7001](0)  master(*)   0-5000
47778f [127.0.0.1:7004](0)    +slave(*)   (slave of 127.0.0.1:7001)
72e796 [127.0.0.1:7002](0)  master(*)   5001-10000
fe9c7d [127.0.0.1:7005](0)    +slave(*)   (slave of 127.0.0.1:7002)
1f340e [127.0.0.1:7003](0)  master(*)   10001-16383
021b80 [127.0.0.1:7006](0)    +slave(*)   (slave of 127.0.0.1:7003)
5982db [127.0.0.1:7007](0)  standalone(*)
[OK] All 16384 slots are covered by 3 masters and 3 slaves.
[OK] All slots are available with 2 replication factor(s)

• NOTICE: This sends INFO keyspace to all nodes.

info

• summarize INFO for each nodes

% rcm -p 7001 info
edb22e [127.0.0.1:7001]  ver(3.2.0), cnt(7633), mem(2.27M;noev;0%), days(0)
f0da61 [127.0.0.1:7002]  ver(3.2.0), cnt(8751), mem(2.61M;noev;0%), days(0)

• arg can be used to select a specific line like grep arg INFO

% rcm -p 7001 info role,cnt,day
edb22e [127.0.0.1:7001]  role(master), cnt(7633), days(0)
f0da61 [127.0.0.1:7002]  role(master), cnt(8751), days(0)

• reserved field names for easy access

  • v , ver , version : delegate to redis_version
  • m , mem , memory : summarize used_memory_human , maxmemory_policy and maxmemory_human
  • cnt, count : extract db0:keys=(\d+)
  • d, day : delegate to uptime_in_days

• NOTICE: This sends INFO to all nodes.

Usage (replication features)

become slave

• meet and replicate (ex. make :7004 slaveof :7001)

% rcm -p 7004 meet 127.0.0.1:7001       # same as "meet :7001" for localhost
% rcm -p 7004 replicate 127.0.0.1:7001  # same as "replicate :7001" for localhost

Usage (utility features)

import

• (experimental) This is too slow deu to step import by one by

% rcm -p 7001 import foo.tsv

Installation

% make
% cp bin/rcm ~/bin/

TODO

• [ ] Dryrun
• [ ] Info
  • [ ] Suggest rebalancing nodes
• [ ] Check
  • [x] Nodes health check
  • [x] Slots coverage check
• [ ] Utils
  • [ ] Rebalance nodes
  • [ ] Bulkinsert on import
  • [ ] Bulkinsert on import
• [ ] Debug
  • [ ] Scan slots

Contributing

1. Fork it ( https://github.com/maiha/rcm.cr/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• maiha maiha - creator, maintainer