Distributed cache service update: redis 4.0, 5.0 and more

Flexible Engine
Release Notes

May 11, 2020

Flexible Engine’s Distributed Cache Service (DCS) in Paris has recieved a major update. DCS is a reliable and scalable Redis cache service fully hosted on Flexible Engine. With distributed technology, DCS supports large-scale, highly-concurrent accesses. Users are now able to upgrade to use this service with the most up-to-date versions of Redis: Redis 4.0 and 5.0.

DCS includes a management console. To use it, sign in to the Flexible Engine Console, select the Paris region (eu-west-0) and access the service.

The DCS help center page has been updated to reflect this update. The page and all of the relevant documentation is available here.

Use cases

DCS with Redis 4.0 / 5.0 will enable :

  • Compatibility with open source Redis: DCS is compatible with open source Redis 4.0/5.0.
  • Compatibility with mainstream programming languages: clients using mainstream programming languages, such as jedis, lettuce, C, python, and Lua are supported.
  • Master/standby HA: when the master cache node fails, the standby cache node takes over automatically.
  • Cluster mode: DCS Cluster instance can support different capacity specifications for 32GB / 64GB / 128GB / 256GB / 512GB / 1024GB for Redis 4.0 / 5.0.
  • Online flexible expansion: Online expansion to higher capacity for single node, master-standby and cluster instances. Single node, master-standby instance support for expansion from 2G to maximum 64G. Cluster instances support for expansion from 32G to maximum 1024G.
  • Data Backup and restore: Data backup and restore for master-standby and Cluster instance. This is the backup service to OBS.
  • Data persistency: Data persistency is provided for cache instances running on master-standby and cluster nodes. This ensures both data reliability and data write/read performance.
  • Authentication: Identity authentication and password mechanism are supported.
  • Single replication: Support select replication amount, one replication or two when creating the DCS 4.0/5.0 Cluster instances.
  • Multiple subnet: Support the create of DCS clusters across subnet.

Support for cluster modes

  • M6 KVM flavors: When creating a Redis cluster, the new KVM m6 flavors are now  from 4 GB to 1024 GB. The New M6 flavors are available in PA3, PA4 and our new Availability Zone (AZ) Eu-west-0c
  • Elastic Volume Service Ultra I/O SSD:  For DCS service, the EVS capacity changes, new Redis cluster for Redis 3, 4 and 5 will rely on Ultra I/O SSD.
    Feature limits: only new clusters will be impacted by this change.
  • Single Replication: Redis Cluster limit master nodes to one replication. Compared to Redis Cluster with double replications, single replication Redis Clusters with one replication is slightly less reliable than Redis Clusters with double replications while remaining cost effective.
    Feature limits: When a node fails, the data in the node’s slot may not be accessed.
    Single replica clusters are only supported for 32GB / 64GB / 128GB / 256GB / 512GB / 1024GB.