Stop writing data to disk in couchbase

Hello,

we are using Couchbase server 2.2.0 on windows environment.I want to stop read and write data on disk.Is there any background service or command through which i can stop disk reading and writing data on disk.

Plz give me reply asap.

Thank you
Jatin

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Hi,

If you use Couchbase buckets, there is no (sane) way to disable disk persistence - it is an integral part of the system and very much needed. You can use memcached buckets, but this comes with (very) different capabilities and is probably not what you were looking for.

What would be the “insane” way?
I might also be interested in not persisting temporary data that I have no problem loosing if reboot happens.

If you don’t have any problem losing data if a failure occurs (your “if reboot happens” falls into this category), then memcached buckets should be fine for you.

Will memcached buckets guarantee data availability as long as there is enough DRAM space or would it “allow itself” to loose data for various reasons, since it’s just supposed to be “cache”?

What Couchbase capabilities do we loose if memcached buckets are used?
Would the data survive cluster reconfiguration? Nodes coming up and down, thus changing hash function etc?
Can we still perform the same queries like on Couchbase buckets?

You actually loose some of the couchbase functionality because they behave exactly like memcached:

  • No replication
  • No persistence
  • No view querying (since that involves the disk as well)
  • No XDCR

So you’re “left” with the key/value type operations, with the exclusion of replicate/persist to as well because of the reasons stated above.

Also, your data will be ejected if the RAM is full (and is removed) and if you add/remove nodes a subset of your cache gets invalid because of how the ketama hashing algorithm works.

Thanks for your reply daschl.

1 Like

Thanks for the reply Daschl

Hi, what about cbepctl | Couchbase Docs? Is that a new way how to do it in latest versions (if we do not calculate with Ephemeral buckets)?