Ephemeral bucket optimal/recommended count


#1

Hi,

I am using couchbase-server-community-5.1.1 server on centos6. I am having 10 ephemeral buckets, with 200MB bucket size for each. I have 3 node cluster with 1 replication factor. Cluster quota is 3000MB per node. I have one custom document type stored in all these buckets.
All these buckets are accessed by a group of services (SOA) with document access (key lookup).
I have around 15k-20k ops/sec hits on the cluster on peak load.

Looking to optimize the number of buckets as suggested in blogs
https://blog.couchbase.com/top-10-things-ops-sys-admin-must-know-about-couchbase/

What would be the suggestion/recommendation for “count” of Ephemeral bucket with above specs. Should it be brought down to 5 or less? Since blog talk about Disk I/O which is not present in ephemeral buckets, should the count be brought down at all?

Any suggestions/recommendations will be appreciated.
Thanks in advance !!


#2

Assuming you don’t have different replication factors, eviction policy, or require different permissions for each set of data, I’d probably just put all the data in a single bucket - and use key prefixing to distinguish between your different types / namespaces.

Note that while Ephemeral doesn’t have disks; there’s still management overhead (managing mutations, DCP replication etc) per bucket; so if you care about maximum efficiency the fewer buckets the better.

(As an aside, each bucket has a fixed memory overhead - I forget the exact numbers but you’ll see an empty ephemeral bucket still consumes ~ <10MB of memory. So if your bucket quota is only 200MB, you’re already wasting ~5% of your memory before you start!)


#3

Thank you :slight_smile: