MSA 2040 - Understanding Volume Tiering

[TigerRool10-1]

Hi There

I've been reading the best practice guide for the 2040 and I'm stumped by volume tiering.

The document seems to be suggesting that "busy" data will "AUTOMATICALLY" move to volumes with a higher Tier - which as far as I can see if physically impossible.

quote from the best practive "As data is later accessed by the host application, data will be moved to the most appropriate tier"

Image if there are two volumes - One is "No Affinity" and one is "Performance".  These two volumes are presented to a Windows 2016 server and mounted as the D: and E: drives.  Imagine that the data on the D: drive started to get very busy - Is the best practice doucment trying to tell me that the data will be moved from the D: drive to the E: drive - that to me seems impossible.  Its actually something you'd never want to happen.

ta

[TigerRool10-1]

To use "Volume Tiering" would anyone know if the Pool that the volume sites on - does that Pool have to be configured with "Standard" and "Performance" disk groups? (forget archive for the moment)

If it does then "Volume Tiering" ....finally.....makes sence.

[SUBHAJIT KHANBARMAN_1]

1st of all there is nothing called "Volume Tiering"

The concepts called "Automated Tiering" and "Volume Tier Affinity".

Now in MSA Virtualization if I assume you have all 3 type of drives likes SSD, Enterprise SAS and  Midline SAS then you can have Performance, Standard and Archive Tier.

We create disk-groups as per the drive types. In this example I assume we have created three different disk-groups as per 3 different drive types.

I assume all these 3 disk-groups part of same Pool

Now when we create Volume of some particular size that time MSA just create that size volume by taking space from that Pool. You will not come to know from which tier or disk-group space or pages will be allocated. This is Virtualization.

Now lets say you have created two volumes. Like you said D and E drives. In Automated Tiering or Volume Tier Affinity data never move between one Volume to another volume. In case of AUtomated Tiering pages moved between one tier to another tier based on usage and hot demand of pages. May be you can go through same Best Practice guide and go through details of "Automated Tiering" to get more details on this.

Now coming to "Volume Tier Affinity"..........this is not like Tier Pinning where pages must move to some particular tier. I would suggest to go through same Best Practice guide and go through "Mechanics of Volume Tier Affinity" . This will give clear idea regarding this.

Hope this helps!
Regards
Subhajit

I am an HPE employee

If you feel this was helpful please click the KUDOS! thumb below!

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[TigerRool10-1]

Ah! I feel a bit daft now!  That makes much better sense.

thanks for assistance.

[SUBHAJIT KHANBARMAN_1 · Accepted solution]

Nice to know that you are happy and satisfied with the answer.

Request you to mark the forum as resolved if there is no more outstanding query from your end on this issue.

This will help for everyone who are all following your forum.

Hope this helps!
Regards
Subhajit

I am an HPE employee

If you feel this was helpful please click the KUDOS! thumb below!

***********************************************************************************

[serviceofthesun]

hi, is it possible to disable tiering?

assume i have sas and sata disks 7200 rpm, and I just need to have it in the same pool, by default msa seems to create tiering with archive tier on sata disk groups