Raid5 second partition alignment?

[hkpolice]

So after the first partition is created, how do you go about aligning the second partition? Does Windows7/Vista do it automatically?

For example, if the stripe size is 64k in a 5 drive Raid5, each full stripe = 256K. What if the first partition is exactly 1152K, that would throw off the alignment of the second partition if Win7/Vista were to use the standard 1024K offset. Or does Windows detect this automatically and will reduce to offset of the second partition?

Thanks

 

[sub.mesa]

Win7/Vista will create the first partition at 1024KiB offset; meaning it works with your 256KiB full stripe block array. However, if you were using 4 drives in RAID5 you would be unaligned with this offset.

So the way Windows 7 and Vista create partitions is good for RAID0 but not always for RAID5 and 6. Using odd number drives for RAID5 or even number drives for RAID6 will help here. Your 256KiB is a very good full stripe block size. However, personally i would go for at least 128KiB stripesize - thus having 512KiB full stripe block.

About your actual question; what about the second partition. I'm not sure, but ideally it would be aligned to 1 megabyte blocks - that would allow full stripe blocks of up to 1 megabyte.