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Dynamic Provisioning: No mouldy beans for me thanks!

As a techie I occasionally come across a technology that I really like, or like the sound of.  One such technology is Enterprise Flash Drives/Solid State Drives .  I really want to get my hands one some and deploy them in anger.  Almost to the point where I would shoehorn it in to a solution just so that I can play with it.....  but obviously Im far too professional to do something like that.

Then there are times when a technology sneaks up on me and I wake up one morning thinking how hideous the world would be without it.

Dynamic Provisioning is in the latter category.

I've been working with Dynamic Provisioning (HDP ) on Hitachi USP V arrays for a year or so now, and while I like it, I have gone on the record in the past as saying that I can take it or leave it.  Well to my surprise, apparently I can't.....

I came home today to an email from a management bod (and one that has impressed me so far) of an outsourced account that I am currently providing storage design and architecture expertise advice for.  The email set out to explain why Hitachi Dynamic Provisioning would not be included in the bundle that I was to create the solution from.  It contained a couple of articles cut and pasted into the email that denounced the evils of thin provisioning (TP), and used them as the basis of why HDP would not be purchased for this solution.

So I took a deep breath and stepped back to think about what this would mean for the design.  We would still be putting in the latest and greatest hardware from Hitachi and Brocade, which would last the company for the next 3-5 years.  But if we left out Dynamic Provisioning, we would be putting into place something in that was already on its way out.  In my reply, I likened it to - nice new tin but with mouldy beans inside.

So I listed some of the advantages of HDP as follows -

  • Greatly simplified LUN management (faster to provision LUNs, less thought required when provisioning, less spreadsheets to manage......)
  • Ability to dynamically grow LUNs (fudging LUNs together with LUSE will become a thing of the past)
  • More efficient Copy and Replication services (only copy real data and not zero data)
  • Zero Page Reclaim after migrations (we will be migrating a lot of hosts and storage to the new kit and could claw back a ton of capacity)
  • Wider back end striping

On top of the above, and Im sure it's the same with the other major players such as EMC and 3PAR etc, it looks to me like Hitachi are ploughing a whole load of R&D into Dynamic Provisioning.  Lets face it, most of the interesting new features that are being released and talked about relate to DP.  This technology is not just a standard speed or capacity hike, it's a game changer and it's getting interesting.

Obviously we expect the vendors to tell use we "need" a certain feature, especially the ones we have to cough up cash for the privilege of using.  But this one is becoming more and more compelling and almost overnight, and without me realising, its become a "must have" for me.

Interestingly, none of the places I have deployed HDP at have wanted to use the oversubscription feature (TP).  In fact they have almost been put off the technology because of the catastrophic possibilities this could bring if left unchecked. 

So might I suggest to the DP vendors out there, if you don't already have the ability to pre-allocate LUNs, or even better, turn off the ability to overprovision form a pool..... get it and get it quick.  People don't really want "thin".

Fortunately the manager involved with the account I mentioned is good enough to understand the business and operational benefits of DP.  But had I not been around, or had he been a cowboy or a "jobsworth", this one might have got away.


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