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View Full Version : [SOLVED] Partition 1 does not end on cylinder boundary



Devan Dean
October 4th, 2011, 08:02 PM
I did a clean install of ubuntu 10.04.3 this morning. I usually use gparted to create the partitions, but decided that this time I would create them during the install process. I also decided to create a /boot partition, which is something I have never done before. The computer boots up with no problems.

I ran sudo fdisk -l and this is the output:
Disk /dev/sda: 120.0 GB, 120034123776 bytes
255 heads, 63 sectors/track, 14593 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000d4e7c

Device Boot Start End Blocks Id System
/dev/sda1 * 1 122 975872 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 122 2554 19530752 83 Linux
/dev/sda3 2554 2797 1952768 82 Linux swap / Solaris
/dev/sda4 2797 4620 14647297 5 Extended

/dev/sda1 is a /boot partition. Is the fact that fdisk says "Partition 1 does not end on cylinder boundary." going to cause problems? I have never seen this before. I don't know if I should start over and used gparted or not. I'd like to solve any problems or potential issues before I spend any more time customizing.

oldfred
October 4th, 2011, 11:50 PM
It is not a problem.

Drives have not used cylinder boundaries since hard drives exceeded 8GB and BIOS uses LBA or large block allocation. But all the partition tools thru Linux & XP installs still followed cylinders so partition tools never changed the error messages.

New partitioning tools with Vista and recent versions of gparted changed partition start from sector 63 to 2048. This improves performance with the new 4K drives & SSDs. Minor loss of a few sectors.

First, understand that most partitioning tools have moved to a policy of aligning partitions on 1 MiB (2048-sector) boundaries as a way of improving performance with some types of RAID arrays and some types of new hard disks (those with 4096-byte physical sectors). See article by srs5694:
http://www.ibm.com/developerworks/linux/library/l-4kb-sector-disks/
Post on 8-sector boundaries alignment by srs5694
http://ubuntuforums.org/showthread.php?t=1685666
http://ubuntuforums.org/showthread.php?t=1768635

Devan Dean
October 5th, 2011, 03:06 PM
Drives have not used cylinder boundaries since hard drives exceeded 8GB and BIOS uses LBA or large block allocation. But all the partition tools thru Linux & XP installs still followed cylinders so partition tools never changed the error messages.

I think I better hurry and catch up!

Thanks for your help. The links you provided have good info that I am following up on. Thanks again.

crtlbreak
January 19th, 2012, 12:50 AM
Another reason (as I have found today!) is that gparted was used to partition the disk when fdisk is called to check the status.
Just thought I would throw in my 10 pebbles worth ;-)