This Essbase discussion board is provided as a free service and dedicated to all the Essbase professionals out there!
  << Previous Topic | Next Topic >>Return to Index  

Question asked by my Infrastructure team

August 16 2012 at 10:45 AM
No score for this post
NM 
from IP address 63.73.199.69

Hello All,

We are in the process of moving Essbase from VMWare to real box due to performance issues. My infra technician asked me if we need 3 disk Raid 5 or 2 disk Raid 1 for Essbase server. Not sure how to weigh them on Essbase side.

Can anyone of you throw some light on it please

Thanks,
Naveen

 
Scoring disabled. You must be logged in to score posts.Respond to this message   
AuthorReply

Jeff McAhren

63.108.38.204

well

No score for this post
August 16 2012, 11:03 AM 

Two or three spindles? Raid 1 and 5 will probably be equally slow.

If performance is important, you need more disks. They're cheap, and will directly affect calc times. I/O is usually the bottleneck for Essbase calcs.

Hopefully they're at least using 15k SAS disks?

 
Scoring disabled. You must be logged in to score posts.Respond to this message   

Jeff McAhren

63.108.38.204

Re: well

No score for this post
August 16 2012, 11:22 AM 

BTW, just as a frame of reference, the last time I used an Essbase server with local storage was back in 2008. It had a mirrored pair for the OS (raid 1), and 10 disks for Essbase configured as raid10 (12 disks total). The Dell guy who built it for us considered:

-- optimal stripe size based on Essbase block size
-- using two raid controller channels to split up the work at a physical level
-- multiple os luns to allow the OS to optimize reads/writes
-- raid alignment (which I was told is critical)

Calcs were more than twice as fast than the former server which had similar RAM and processors, but a 5 disk RAID5 set.

 
Scoring disabled. You must be logged in to score posts.Respond to this message   
John A. Booth

98.212.120.113

Based on my testing...

No score for this post
August 16 2012, 11:21 AM 

Based on my testing you need to support at least 2500 IOPS per processor core. If you had 8 physical (non hyperthreaded) cores this is 20,000 IOPS. When you get to these speeds you leave physical disks in the dust very quickly.

Look at either Intel 910 SSD or Fusion I/O to really give the amount of IOPS to fully utilize your processors.

If you think about the pure number of physical disks to meeting 20,000 IOPS you start to need over 50 physical disks using at least RAID 10 and even then you are hitting less than 5,000 IOPS so are still a far cry from the amount of bandwidth you require. Never even think about RAID 5 for Hyperion as it has some well known severe performance penalties (up to 4 x) -- this 4 x means you need 4 times the drives to get the equivalent read/write capabilities of 1 real physical drive.

Regards,

John A. Booth
http://www.metavero.com

 
Scoring disabled. You must be logged in to score posts.Respond to this message   
John A. Booth

98.212.120.113

Other considerations

No score for this post
August 16 2012, 11:30 AM 

You need to also consider depending on the controllers and storage infrastructure the number of IOPS you get can vary drastically. For instance I have a RAID 0 (not good for production) with 8 near line sata drives using a LSI 9280-e controller connected with dual mini SAS connectors to my external array. I can get 15,000 IOPS with this configuration. To get equivalent with a RAID 10 configuration you would need at least 16 drives. The LSI controller also performs some "magic" in that it's bundling up small sized IOs like Essbase uses (8 kb size) and making them much larger in order to gain maximum performance. Not all controllers will do this type of thing.

Testing with a tool like IOMETER to really understand the number of IOPS your specific configuration will deliver is best. Hands-down no amount of physical drives will give you more IOPS than PCI SSD technologies.

Regards,

John A. Booth
http://www.metavero.com

 
Scoring disabled. You must be logged in to score posts.Respond to this message   

Jeff McAhren

63.108.38.204

What kind of car are you driving?

No score for this post
August 16 2012, 11:50 AM 

As I look at the question again, I think NM is driving a Tata Nano, and would be lucky to upgrade to a Hyundai Accent or maybe a low mileage used Civic.

I'm probably suggesting a Ford Explorer, and John, I think you're talking about a Aston Martin Vanquish!

;)

 
Scoring disabled. You must be logged in to score posts.Respond to this message   
John A. Booth

98.212.120.113

Re: What kind of car are you driving?

No score for this post
August 16 2012, 12:01 PM 

The real question is do you spend $10,000 on enterprise level SAS drives or $2,500 on an Intel PCI SSD drive.

There are pro's and con's to each solution.

You get maximum performance out of the PCI configuration for less $. The RAID 10 configuration of enterprise drives give you a nice comfort for a single drive failure. With the drives you have to worry about your infrastructure team doing optimal configuration. With the SSD solution it just works and it's as fast as it every will be (no disk bottleneck ever).

If you opt for the drives you may also consider use of Direct I/O -- one client had a SAN where the IT team swore the SAN was great however for whatever reason an 9.3 -> 11.1.2 just didn't perform properly. We had sufficient ram to use Direct I/O and turned that on and had an immediate 10 x performance. Later on the IT team asked the Essbase owner if they would consider something like Fusion I/O in order to stop beating so hard on the SAN.

The question you have to ask and balance is ultimate performance vs standards vs affordability. Knowing what I know now I would never put Essbase on less than 16 RAID 10 drives on a configuration supporting any significant amount of users. If you are a small shop with < 25 users it's not nearly as important. If you start needing to scale out hundreds of users on a planning system which you have 10-30 calcs running concurrently it's of huge importance to have the fasts IO possible.

Your mileage will vary depending on your specific hardware,

John A. Booth
http://www.metavero.com

 
Scoring disabled. You must be logged in to score posts.Respond to this message   

Jeff McAhren

63.108.38.204

Re: What kind of car are you driving?

No score for this post
August 16 2012, 12:14 PM 

Yeah, it probably comes down to money. My post was prompted by the fact that OP's question was "2 or 3 spindles?", not, "what other options should I look at?". We both answered the later.

Your post does make me wonder what his/her user base and app profile looks like.

 
Scoring disabled. You must be logged in to score posts.Respond to this message   
DanP

65.248.232.253

Temp TableSpace

No score for this post
August 16 2012, 1:06 PM 

If nothing else get single spindle local hard drive (or SSD) for your temp tablespaces.

Other than memory this should be the first item on your wish list. If Only xxx dollarsw for SSD then spend them here.

Oh yes and don't forget to configure your apps to use it!!!

 
Scoring disabled. You must be logged in to score posts.Respond to this message   
 
  << Previous Topic | Next Topic >>Return to Index  

RSS feed for this forum - http://www.network54.com/Forum/58296?xml=rss. Please email hypess (at) gmail.com, if you have any questions/feedback/issues.