Can we enable inline deduplication and post process deduplication at the same time?

  • 28 November 2014
  • 8 replies
  • 9287 views

Badge +9
Can we enable inline deduplication and post process deduplication at the same time?

8 replies

Userlevel 4
Badge +18
You can enable both at the same time but if both are enabled you need to have 32 GB of RAM for each CVM. By default when no compresssion or deduplication is enabled, CVM have 16 GB of RAM.

Inline Deduplication (Fingerprint on write) enables performance improvements by intelligently deduplicating data in the SSD tiers and it is recommended for full-clone/persistent desktops/physical to virtual migration use cases. Turning deduplication on for VAAI clone or Linked clone environments is not recommended. It is further recommended that CVMs have at least 24GB of RAM.

Where as post process deduplication is enabled for capacity savings across all tiers - RAM, SSD, & Hard Disk. This option is primarily recommended for full-clone/persistent desktops/physical to virtual migration use cases that need storage capacity savings (not just performance savings from deduplication). It is further recommended that the CVMs have at least 32GB of RAM and 300GB SSDs for the metadata disk to use this option.

Hope it answers your query.
Userlevel 2
Badge +14
Also please keep in mind that you need a Pro or Ultimate license for the post-process compression and dedupe, it is not included in Starter.
Badge +2
What happen if we enable inline compression, inline deduplication and post-process deduplication at the same time? I see saving with inline compression and inline deduplication, but only 1.01:1 saving for post-process deduplication, is it common?
Userlevel 4
Badge +18
When compression is enabled, deduplication will not take effect.

As far as post process deduplication is concerned, please check below mentioned KB. It might be the reason for your issue.

https://portal.nutanix.com/#/page/kbs/details?targetId=kA0600000008fMHCAY
Userlevel 7
Badge +30
Note, as of NOS 4.5 you can run both dedupe and compression at the same time, and it will work as expected. I'm running all of the data features in my lab (compression, both dedup, and erasure coding) as well as several of customers, and it works great.
Badge +4
error while enabling deduplication on capacity tier. Error "post process deduplication cannot be enabled when the feature is disabled in the cluster." able to eanle cache dedupliction/compression.
I have XC630 four node cluster with AOS version 5.1.0.3 and hypervisor is esxi 6.0 U3c. Each CVM is configured with 32 GB ram and 8 vCPUs.
Userlevel 7
Badge +30
please submit a support ticket and we'll get you sorted out
Badge +4
issue got fixed editing given parameter

ncli cluster edit-params enable-on-disk-dedup=true

so run this command on any CVM and you should be able to enable dedupe on capacity tier

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