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Is there anything I can do to speed up the creation of the HP Smart Array logical drives?

Does creating too many drives at the same time affect the overall performance?

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How many logical drives are you creating? Can you provide details on the OS, controller type and RAID configurations you're trying to achieve? –  ewwhite May 23 '11 at 15:19
    
13 RAID5 arrays. 45x 600 GB drives. There are two MSA's on one Controller –  makerofthings7 May 23 '11 at 15:24
    
Wow, that's a lot of RAID5 arrays. I'd start to worry about production performance if you have lots of writes (lots of overhead for the controller to calculate parity & distribute the data). –  voretaq7 May 23 '11 at 15:29
    
Also trying to create 13 arrays at once may be getting to the point where the controller is overworked -- If you have to do this on a bunch of machines you can empirically test it (create all 13 at once on machine A, 5 at a time on machine B, etc...) –  voretaq7 May 23 '11 at 15:30
    
MSA70 units? What's the OS type? Are you doing this from the BIOS utility or from within the GUI tool? –  ewwhite May 23 '11 at 15:31

3 Answers 3

up vote 2 down vote accepted

The most effective way to speed up array creation (all other things being equal, and assuming you're not trying to initialize so many arrays that you're saturating the controller's bandwidth) is to install faster disks.

Re: creating too many drives hurting performance - Definitely possible, but I'm not sure what the point of diminishing returns here would be (it's at whatever point the disk bandwidth is saturated, or the controller is "overworked" and letting drives sit idle for a few milliseconds between issuing commands -- perhaps an HP storage expert could be more specific...)

Remember that array initialization is normally a one-time event - If you can complete an array rebuild within a reasonable time and the overall performance of the system is acceptable when it goes into production it may not be such a terrible thing to have a slow process that only happens once in the life of a system...

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I wouldn't be using a P411 for this, I'd be using a P812.

I have a LOT of MSA70's and although my usage is different from yours and the 411 supports that many logical disks doesn't mean it's the best kit for the job. I use the 812's simply because they handle so much more concurrent workload - whether that's creating multiple logical disks at once or, more importantly for me, handling thousands of concurrent requests I'd go with the 812 every time.

As for your questions? No there's nothing you can do to speed it up once it's got going and yes creating multiple simultaneously will be slower than doing them sequentially.

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What's your thought on the multiple physical arrays versus logical drives in this case? –  ewwhite May 23 '11 at 16:13
    
I'd glossed-over that to be honest - daft idea, one big array, multiple logical disks (or OS partitions if needed at all). –  Chopper3 May 23 '11 at 16:22

Maybe I'm off-base here, but I'm not sure which type of MSA unit this is. But if these arrays are to belong to a single server, would it make sense to create an array consisting of a large number of disks, then create smaller logical drives of the RAID-level and size required, leveraging the Smart Array's unique capability of mixing and matching RAID levels within a given array?

Edit - Also, do you have an option for RAID 1+0? Wouldn't the creation time be faster and the resulting arrays be more performant?

e.g. here's the output of a 6-disk array containing multiple logical drives.

=> ctrl all show config 

Smart Array P410i in Slot 0 (Embedded)    (sn: 5001438009C2A5C0)

   array A (SAS, Unused Space: 583895 MB)


      logicaldrive 1 (100.0 GB, RAID 1+0, OK)
      logicaldrive 2 (10.0 GB, RAID 1+0, OK)
      logicaldrive 3 (5.0 GB, RAID 1+0, OK)
      logicaldrive 4 (5.0 GB, RAID 1+0, OK)
      logicaldrive 5 (10.0 GB, RAID 0, OK)

      physicaldrive 1I:1:5 (port 1I:box 1:bay 5, SAS, 146 GB, OK)
      physicaldrive 1I:1:6 (port 1I:box 1:bay 6, SAS, 146 GB, OK)
      physicaldrive 1I:1:7 (port 1I:box 1:bay 7, SAS, 146 GB, OK)
      physicaldrive 2I:1:1 (port 2I:box 1:bay 1, SAS, 146 GB, OK)
      physicaldrive 2I:1:2 (port 2I:box 1:bay 2, SAS, 146 GB, OK)
      physicaldrive 2I:1:3 (port 2I:box 1:bay 3, SAS, 146 GB, OK)

   SEP (Vendor ID PMCSIERA, Model  SRC 8x6G) 250 (WWID: 5001438009C2A5CF)
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This is an MSA D2700 –  makerofthings7 May 23 '11 at 16:05
    
I'm doing this for an Exchange 2010 server, and using partitions to isolate IO traffic, and create a single physical unit of Performance and Failure per database –  makerofthings7 May 23 '11 at 16:07
    
Are you creating multiple physical arrays OR are you creating multiple logical drives? –  ewwhite May 23 '11 at 16:10
    
Logical Drives. I just cleaned up my question; –  makerofthings7 May 23 '11 at 16:14

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