I have a n5200 and a n5200 Pro NAS box.
According to Thecus only a limited set of HDDs are supported, at most 1.5Tb - this could possibly due to the 4k sector size....
Sadly, some HDDs are aligned on 4k sectors - and these are usually the newer 2Tb drives. Older drives, are aligned to 512byte sectors. If 512 byte data has to be written across two physical 4KB blocks, the hard drive will have to read the 4KB blocks that are affected, introduce the modifications, and write them back onto the drive.
Windows Vista and Windows 7 are sector-aware, meaning they will automatically align 512 byte sectors with the hard drive’s physical sectors starting at LBA block 2048. Xp doesn't have this, and starts writing at LBA sector number 63, all following sectors will be misaligned, causing a noticeable performance impact.
There is a more detailed article here: Linux on 4KB-sector disks
So basically - under linux, issue this:
What a pain this issue is.... but if you don't align the sectors, you could be getting 10-15MB/s instead of 35-45MB/s
According to Thecus only a limited set of HDDs are supported, at most 1.5Tb - this could possibly due to the 4k sector size....
Sadly, some HDDs are aligned on 4k sectors - and these are usually the newer 2Tb drives. Older drives, are aligned to 512byte sectors. If 512 byte data has to be written across two physical 4KB blocks, the hard drive will have to read the 4KB blocks that are affected, introduce the modifications, and write them back onto the drive.
Windows Vista and Windows 7 are sector-aware, meaning they will automatically align 512 byte sectors with the hard drive’s physical sectors starting at LBA block 2048. Xp doesn't have this, and starts writing at LBA sector number 63, all following sectors will be misaligned, causing a noticeable performance impact.
There is a more detailed article here: Linux on 4KB-sector disks
So basically - under linux, issue this:
fdisk -H 224 -S 56 /dev/sdaWhat a pain this issue is.... but if you don't align the sectors, you could be getting 10-15MB/s instead of 35-45MB/s
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