I recently bought a 1 TB Advance Format HDD for my home computer and partition it up so I can run Windows 7, Slackware, Xubuntu and some other distros that I would like to try out. I used parted to make partitions that were physically align with my AF HDD sectors. Everything seemed to be ok until after I installed my distos onto the logical partitions. The following is what I got.
Code:
root@ampatu:~# fdisk -l
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x000ecb04
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 532482047 266240000 7 HPFS/NTFS/exFAT
/dev/sda2 532486142 1923123199 695318529 f W95 Ext'd (LBA)
Partition 2 does not start on physical sector boundary.
/dev/sda5 532486144 534583295 1048576 82 Linux swap
/dev/sda6 534585344 591929343 28672000 83 Linux
/dev/sda7 591931392 837691391 122880000 83 Linux
/dev/sda8 837693440 1001533439 81920000 83 Linux
/dev/sda9 1001535488 1062975487 30720000 83 Linux
/dev/sda10 1062977536 1472577535 204800000 83 Linux
/dev/sda11 1472579584 1923123199 225271808 7 HPFS/NTFS/exFAT
root@ampatu:~#
My extended partition is no longer aligned. Partition 1 (sda1) is home to Windows 7 and I did verify that all my partitions were still align after the Win7 installed. I then proceeded with Slackware and Xubuntu install and afterwards found the mis-alignment. This was my second attempt. My first try also resulted in the same "extended partition not aligned" error. On my 2nd attempt, I added an extra 2048 kB of space between partitions thinking maybe the EPBR (extended partition boot record) was using up space when I was installing distros into my logical partitions. I search the web and didn't find much info. So my question arises.
Why does my starting sector on my extended partition change after I install Xubuntu (sda8) and Slackware (sda6/7)? Originally, sda2 started at sector 532484096.
Is there a way to keep my starting sector from changing thus remaining physically aligned?
My web searches yield a "
don't worry 'bout it" answer for mis-aligned extended partitions as long as the logical partitions remained aligned. Why is this the case? If we have to go thru the EPBR table on a mis-aligned partition to find our files on a perfectly aligned logical partition, don't we still get hit with the mis-align penalty?
Maybe I'm putting to much thought into this but It's been bugging me lately. I probably should get a girlfriend...
