Given the long time did not go over things used today, the interview was asked miserably, not not (in fact, forget) is a time did not know how to say (very embarrassing), then simply order a bit today interviewer asked Some questions about codis for reference purposes only
What codis that?
Redis is a distributed clustering solutions
What are the components contained?
dashboard, codis-proxy, fe, codis-server (zookeeper premise)
Each component role?
dashboard: You can add or delete redis and proxy nodes, add and delete group, etc.
codis-proxy: processing client requests
fe: simple management control interface
codis-server: Codis Redis project maintenance of a branch, based on the development of 2.8.21, adding support for instructions and data migration of atoms slot (than the official explanation)
codis advantages and disadvantages?
codis advantages:
1. Support for online data migration (slot merger), simple management and monitoring interface
2. Because it is distributed clusters, data storage and high availability agent nodes
3. automatically assigned to each set of data uniformly
4. The relatively large storage capacity, since the maximum support 1024 redis Examples
codis disadvantages:
1. Domestic revenue, activity is not high, but very easy to use
2. Only a proxy agent node when codis-server performance may decline
3.codis comes redis redis with the original may not be compatible
Why Packet?
To add the master (cross arrangement), ensures that no data is lost while the node goes down, so that even if downtime, data in another table is complete, the data can be recovered by the migrated
About codis probably asked that so much, thank you! !
