Multiple disk group pros/cons

hello all,
This is with regards to 11.2.0.3 DB(RAC) on RHEL 6
i am trying to identify the pro's/con's of using multiple ASM Diskgroup. I understand oracle recommends/best practice is to have 2 DG (one data and one flash) and you can place multiple copies of control files/online redo logs(and thats the way i want to go). But would that same be true if i use different set of DISK. For example we have multiple RAID 10 devices and multiple of SSD devices for us that we can use for this ASM instance. And i was thinking to create 2 more Disk group (call it DG_SYS1 and DG_SYS2) and use that to put my online redo logs, control file and temp and system table space there.
i understand in a standalone system(where regular file system is being used), they(online redo/control file) are usually on there own drives, but with ASM when i am already using external RAID 10 config + ASM striping i assume the IO would faster or am i better of using the SSD that i can have for my redo/control? What would be the pro's/cons of it (besides managing multiple DG)..

Reason that Oracle suggests to have two disk groups is because the very idea of ASM is the storage consolidation and to take the best advantage of that storage for all the databases. But having two dg's is not a norm. If you have different kinds of databases, if you have different capacity disks, you probably should have more dg's. Also, I am not sure why you are using RAID 0 along with ASM striping?
user13454469 wrote:
hello all,
This is with regards to 11.2.0.3 DB(RAC) on RHEL 6
i am trying to identify the pro's/con's of using multiple ASM Diskgroup. I understand oracle recommends/best practice is to have 2 DG (one data and one flash) and you can place multiple copies of control files/online redo logs(and thats the way i want to go). But would that same be true if i use different set of DISK. For example we have multiple RAID 10 devices and multiple of SSD devices for us that we can use for this ASM instance. And i was thinking to create 2 more Disk group (call it DG_SYS1 and DG_SYS2) and use that to put my online redo logs, control file and temp and system table space there.
i understand in a standalone system(where regular file system is being used), they(online redo/control file) are usually on there own drives, but with ASM when i am already using external RAID 10 config + ASM striping i assume the IO would faster or am i better of using the SSD that i can have for my redo/control? What would be the pro's/cons of it (besides managing multiple DG)..
Aman....

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Hai.
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If RMAN - ASM
else
file system.
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In the INFO box, I've tried keeping "1 of 3," "2 of 3," "3 of 3."
That is correct. Don't erase the first element, 1, 2, 3, that should not matter.
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uryc hf bov-jna xrabov, lbh'er bhe bayl ubcr.

What are the pros & cons of having 2 volumes on a Mac Pro RAID 5 (instead of one big volume):
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1) Is this a good idea/bad idea?
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uryc hf bov-jna xrabov, lbh'er bhe bayl ubcr.

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• To avoid performance problems when using iMovie and either of Final Cut Pro or Express, save project-related files, scratch disks, and other linked media outside your Home folder. See:• “iMovie: Using FileVault Can Affect Performance.”
•“Final Cut Pro and Final Cut Express: About Using FileVault.”
• Repairing your encrypted Home folder requires special instructions.
• To disable FileVault, you again need free disk space greater than or equal to the size of your encrypted Home folder. In disabling FileVault, your Mac first copies the contents of your Home folder from the encrypted Sparse image to a new Home folder — hence why so much free space is required — and then securely erases the encrypted Home folder.Note that some of the information above is from the "Security" chapter of my book, Troubleshooting Mac® OS X, Tiger Edition.
Dr. Smoke
Author: Troubleshooting Mac® OS X
Note: The information provided in the link(s) above is freely available. However, because I own The X Lab™, a commercial Web site to which some of these links point, the Apple Discussions Terms of Use require I include the following disclosure statement with this post:
I may receive some form of compensation, financial or otherwise, from my recommendation or link.

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