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View Full Version : [ubuntu] software striping on SSDs... dumb idea?



dreamgear
August 27th, 2012, 11:07 PM
I bought a new server with a supermicro X9SCL mb, which came with two 128MB SATA SSDs. Out of the box they were set up as a stripe set.

I just took the defaults as I installed Precise on it, and find that my disk is called /dev/mapper/blahblahblah, indicating this is a "fakeraid" device.

Is there any point in this arrangement ? Am I getting any improvement in performance for my trouble? If so, as I understand it the price I pay is a reduction in MTBF, since if either of these devices quit I will need to rebuild.

Thanks in advance for your thoughts.

darkod
August 27th, 2012, 11:11 PM
Well, with raid0 (striping) you get no redundancy. If one disk goes, all the data is gone since you can't recover from the remaining disk.

I am not sure it will decrease SSD life if that's what you are worried about, but I would host any important data on raid0. Of course, you can make regular backups on another medium, and keep working on raid0 if you want to.

dreamgear
August 29th, 2012, 03:06 AM
I guess what I really want to know is there any upside to this? Will I get improved performance?

shreepads
August 29th, 2012, 07:43 AM
I guess what I really want to know is there any upside to this? Will I get improved performance?
Depends on what you're running, but from what I can see online, this board only has SATA II support, so if the two 128GB (not MB I assume) SSDs are SATA III capable and capable of saturating a SATA II interface then yes this setup will deliver higher IOPS.

Whether that translates into better performance depends on what you're running.

dreamgear
August 30th, 2012, 02:31 PM
Depends on what you're running, but from what I can see online, this board only has SATA II support, so if the two 128GB (not MB I assume) SSDs are SATA III capable and capable of saturating a SATA II interface then yes this setup will deliver higher IOPS.

Whether that translates into better performance depends on what you're running.
Thanks. Well, I may stop making the MB/GB/TB mistake before I retire. Took me 20 years to stop saying KB when I meant MB.