Hi,
Thank you for using Couchbase and I’m sorry to see the issues you are encountering.
And thank you for the detailed problem description.
Based on what you provided, here are a few of my thoughts:
- Because you are not using index/query, I recommend only enabling data service on all nodes. Corresponding, index RAM quota can be set to 0.
- It seems that this issue only happens during rebalance. It seems to me that is caused by high memory pressure from memcached which resulted in eviction malfunction. We have a sizing guide here: http://developer.couchbase.com/documentation/server/current/install/sizing-general.html. Even though 4GB is the recommended min RAM quota, I would recommend increasing that based on what you observed in the cluster.
- When you say, you have 2 replicas of data, do you mean, you have 1 master + 1 replica or 1 master + 2 replica? In most use cases, setting # of replica = 1 is good enough. Setting # of replica to 2 will increase RAM pressure.
Thanks,
Qi