Performance increase with new SATA controller possible?

[opentoe]

I'm using (the very popular to unraid users) SuperMicro AOC-SASLP-MV8 PCI-E x4 controller card. The card has been full since I installed with all 7200 rpm 2TB drives. All the drives are 300Gb speed, and that is what the card is also.

 

Has anyone upgraded their controller card to a 6Gb controller and gotten better performance? I'm not speaking of leaps and bounds, but maybe a little more snappy and quicker when searching/browsing through folders and stuff like that. What is the logical upgrade to the particular card I'm using now? There isn't a clear upgrade path and eventually when I do upgrade the entire machine I will make sure everything is and will be using a 6Gb speed connection. Drives and controller to get the best performance. I know the killer is that parity/write speed, but if the controller and drive are at 6Gb, how fast does the write speeds increase to?

 

I'm using the latest beta.

 

I just checked Supermicro's website and they have the AOC-SAS2LP-MV8 card. It is basically similar to the 3Gbit version, but this model is 6Gbit speed. Is anyone using this card right now with unraid?

 

http://www.supermicro.com/products/accessories/addon/aoc-sas2lp-mv8.cfm

 

 

 

 

[cassiusdrow]

The SuperMicro AOC-SASLP-MV8 controller card is a PCI-Express v1 x4 card with SATA II ports.  I will assume the 8 hard drives connected to it are also SATA II drives.  While a SATA II connection provides 3 gigabits/second (300 megabytes/second) of bandwidth, each hard drive can only physically deliver at most about 130 megabytes/second, so a SATA II connection is more than adequate.  In order for all 8 hard drives to deliver their maximum bandwidth, a PCI-Express connection needs to provide 1040 megabytes/second of bandwidth.  A PCI-Express v1 x4 provides 1000 megabytes/second of bandwidth, just slightly under the amount needed. 

 

The SuperMicro AOC-SAS2LP-MV8 controller card is a PCI-Express v2 x8 card with SATA III ports.  SATA III makes no improvement using hard drives, because SATAII is already more than needed.  However, PCI-Express v2 x8 will provide 4000 megabytes/second of bandwidth, far more than the 1040 megabytes/second of bandwidth need by the 8 hard drives.

 

There will be a slight benefit because of the PCI-E upgrade, but I doubt it would be too noticeable in everyday use.  You parity check speed may improve slightly.