File System Analytics

[TMADOCTHOMAS]

We just upgraded to 9.8 and I'm interested in implementing the new File System Analytics feature (we will be upgrading again to 9.9.1 in a few weeks so that will give us the formerly-7-mode volumes as well). My primary use case would be to see which data isn't being used and possibly do away with it or at the very least archive it. In particular I'm interested in the following:

• Are there any performance concerns around running this tool? Our primary cluster is an AFF A700, but we also have a couple of older/smaller FAS systems (2620, 2720) and an OnTAP Select system.
• I primarily see the benefit in running these against our numerous CIFS Servers. Is there any reason/benefit to also run them against our NFS datastores? 

Plus, would love to hear any other real-world thoughts / suggestions from someone who has used this feature. Thanks in advance!

[hmoubara]

Hello TMADOCTHOMAS,

i have not used that option to give you any thoughts or suggestions, but i hope the below link can help answer your questions:

Considerations for File System Analytics

https://docs.netapp.com/us-en/ontap/file-system-analytics/considerations-concept.html

File System Analytics overview

https://docs.netapp.com/us-en/ontap/concept_nas_file_system_analytics_overview.html#learn-more-about-file-system-analytics 

Thanks 

[BradenP · Accepted solution]

Hi TMADOCTHOMAS,

In terms of the performance impact of using File System Analytics (FSA), I would stager enabling FSA on one or two volumes at a time and monitor how the system reacts, especially for your older systems and your Select system. This way you can verify if you are starting to see and slowness in the system when enabling FSA.

• 1. Monitor performance of CPU using the sysstat and qos statistics commands outlined in this KB
  2. Enable for one volume, and reassess load
  3. If load does not increase, add one or two more volumes
  4. If load or latency starts to increase beyond acceptable levels, do not enable more volumes
  5. Monitor progress with the volume analytics show command:
     1. Ensure the scan is finished
     2. The state is on
     3. Start the scan on more volumes
• Do not enable analytics if maximal performance is required as outlined in the File System Analytics overview and considerations
• If the performance is unacceptable, disable analytics for the impacted volume.

Reference KB:

https://kb.netapp.com/Advice_and_Troubleshooting/Data_Storage_Software/ONTAP_OS/High_or_fluctuating_latency_after_turning_on_NetApp_ONTAP_File_System_...

[parisi]

My understanding is that the perf impact is up to 10% on initial scan but not much at all afterwards unless you have a ton of data churn. It's also opportunistic, meaning it works as a lower priority job.

We talk about performance impact in this podcast:

https://soundcloud.com/techontap_podcast/episode-270-netapp-ontap-file-systems-analytics

[TMADOCTHOMAS]

Thank you @hmoubara and @BradenP ! The KB in particular is just what I was looking for as it outlines clearly the potential issues and how to work through them. Thank you again!

[TMADOCTHOMAS]

Thank you @parisi ! I will give the podcast a listen. Very helpful information about how the job works.

[paul_stejskal]

FSA is a great feature but if you have millions or billions of inodes, it seems to affect some volumes or all volumes. Improvements are coming but if you have an issue please log a case so we can escalate with CPE.

[TMADOCTHOMAS]

Will do, thank you @paul_stejskal ! I will at least wait to implement until we upgrade to 9.9.1 in a few weeks. We only have one volume with a lot of inodes. I've had to increase inodes on it in the past several times. I'll probably save it for last.

[paul_stejskal]

I understand. Maybe you'll need to break it up.