mesasinmantel wrote:What is faster: 1 big array of 8 HD in RAID 5 or (2) arrays of 4 HD each? - always using (2) netwoerk connections
really, it depends mostly on the type of workload, and how much space you need for the volume.
if you can spread out the load on 2 separate arrays, then in theory you're potentionally increasing the total possible performance because either array are not sharing the load (or lack of) the other.
The individual performance may or may not be of much difference, and if you need a volume of more than 5.5tb (4x 2tb raid5), then your only option is a big array of 8 anyway.
if space is not a problem, another option is raid 10 instead of raid5.
I would suggest the only best true answer you can find is by testing with your disks and the workload(s) you need to use, with the various modes available.
nv+ ~ 1gb ram ~ 4x WDC WD20EARS-00S8B1 ~ 5555 GB
ultra4 ~ 4 gb ram ~ 2x ST31500341AS ~ 2x ST4000DX000-1C5160 ~ 6471 GB
pro business ~ 4gb ram ~ dual redundancy ~ 4x Hitachi HDS724040ALE640 ~ 2x SAMSUNG HD204UI ~ 9130 GB
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