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I was recommended to use Ubuntu instead of XP to partition my new SSD. However, I didn't find diskpar
, so I used GParted. The partition table type is msdos, fdisk reports the following:
Device Boot Start End Blocks Id System
/dev/sdc1 63 67119569 33559753+ 7 HPFS/NTFS
/dev/sdc2 67121152 134227967 33553408 83 Linux
Disk /dev/sdc: 255 heads, 63 sectors, 15566 cylinders
Nr AF Hd Sec Cyl Hd Sec Cyl Start Size ID
1 00 1 1 0 254 63 1023 63 67119507 07
2 00 254 63 1023 254 63 1023 67121152 67106816 83
3 00 0 0 0 0 0 0 0 0 00
4 00 0 0 0 0 0 0 0 0 00
Is this correct? Given all those odd numbers, I don't think so, but I have no idea. There are no data there yet, so I can throw it all away, I need to tool for moving partitions.
EDIT:
According to this post, it's wrong.
EDIT2:
The problem:
I edited the question in order to present what I've learned. Partition alignment is no hoax. The first sector is the boot sector, whenever your partitions starts immediately after it, it has an offset of 512 bytes from the beginning. An OS uses clusters which consist of multiple sectors, e.g., 1 cluster = 8 sectors = 4096 B. A cluster is the least unit an OS cares about.
An SSD uses a page size (typically 4 KiB, AFAIK) as the least writable unit.
- Assuming these sizes, in the aligned case, whenever the OS writes a cluster, it corresponds with the SSD page. The SSD just writes the page.
- In the misaligned case, it spans two pages. The SSD must read-modify-write two pages!
My partitioning:
I used fdisk and ignored the whole cylinders/heads crap. I set the offset of the first partition to 1 MiB (i.e., 2048 sectors) and it's size to 30 GiB (which is easily done by entering +30G). For the following partitions I kept the default offset and set the size to multiples of 1 GiB. Everything looks fine, except for (G)Parted crashing immediately when starting. According to the calculator it's alright for all realistic SSD parameters I entered. Both Windows and Linux can access the partition, so I think nobody cares about cylinders anymore.
The right answer is in the question now. – maaartinus – 2011-02-07T17:25:36.493