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robgraves
May 8th, 2011, 03:01 AM
i ran the fsck -l command, output here:


robgraves@ubuntu:~$ sudo fdisk -l

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 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: 0xf1977e89

Device Boot Start End Blocks Id System
/dev/sda1 * 1 26 203776 7 HPFS/NTFS
Partition 1 does not end on cylinder boundary.
/dev/sda2 26 25680 206062592 7 HPFS/NTFS
/dev/sda3 25680 57914 258922496 5 Extended
/dev/sda4 57927 60789 22987776 7 HPFS/NTFS
/dev/sda5 36136 56844 166339584 83 Linux
/dev/sda6 56870 57914 8388608 82 Linux swap / Solaris
/dev/sda7 25692 36136 83886080 83 Linux

Partition table entries are not in disk order
robgraves@ubuntu:~$ what concerns me is this portion:


/dev/sda1 * 1 26 203776 7 HPFS/NTFS
Partition 1 does not end on cylinder boundary.

This, i believe, is the boot partition that windows had setup on my hard drive long before i ever did anything to it, as windows 7 came pre-installed on my computer.

Is partition 1 not ending on a cylinder boundary a reason for concern?

How did that occur?

And if it is a concern, what is the easiest way to fix this?

Thanks in advance.

tgalati4
May 8th, 2011, 03:12 AM
No problem. Partitions that end on a boundary are a little more efficient for read-ahead, caching algorithms. GParted will normally create partitions that end on a cylinder boundary.

With Windows, who knows?

It's doubtful that you will be touching the Windows partition much while in Linux. So it's just a warning and nothing to worry about.

robgraves
May 8th, 2011, 03:26 AM
cool, thank you, i saw that and it had me worried.

srs5694
May 8th, 2011, 05:13 AM
Actually, the speed advantages of partitions ending on cylinder boundaries haven't applied for well over a decade. In fact, the cylinder/head/sector (CHS) geometries reported by today's hard disks are fictions created to keep the BIOS and other CHS-using tools happy; the actual physical layout of partitions on a disk bears little resemblance to what the disks report.

Partitioning tools today have moved to a new policy of aligning partitions on 1 MiB boundaries. This improves performance with certain types of modern storage device, including Advanced Format disks, SSDs, and some types of RAID arrays. (See this article (http://www.ibm.com/developerworks/linux/library/l-4kb-sector-disks/) I wrote on the topic of partition alignment on Advanced Format disks.) The latest versions of GParted now align partitions on 1 MiB boundaries by default, not on cylinder boundaries. This change was fairly recent, though (within the last year or two, although of course the version shipped with Ubuntu inevitably lags a bit).

The fdisk warning about a partition not ending on a cylinder boundary might have been relevant in the arly 1990s, and might even be relevant today if you were running a very old version of DOS; but for most users it's irrelevant. If you've got a disk that uses a technology that works best with a power-of-2 4 KiB to 1 MiB alignment, you must examine the start sector (not the starting or ending cylinder) and determine if the value is divisible by the appropriate number.

robgraves
May 8th, 2011, 05:18 AM
Actually, the speed advantages of partitions ending on cylinder boundaries haven't applied for well over a decade. In fact, the cylinder/head/sector (CHS) geometries reported by today's hard disks are fictions created to keep the BIOS and other CHS-using tools happy; the actual physical layout of partitions on a disk bears little resemblance to what the disks report.

Partitioning tools today have moved to a new policy of aligning partitions on 1 MiB boundaries. This improves performance with certain types of modern storage device, including Advanced Format disks, SSDs, and some types of RAID arrays. (See this article (http://www.ibm.com/developerworks/linux/library/l-4kb-sector-disks/) I wrote on the topic of partition alignment on Advanced Format disks.) The latest versions of GParted now align partitions on 1 MiB boundaries by default, not on cylinder boundaries. This change was fairly recent, though (within the last year or two, although of course the version shipped with Ubuntu inevitably lags a bit).

The fdisk warning about a partition not ending on a cylinder boundary might have been relevant in the arly 1990s, and might even be relevant today if you were running a very old version of DOS; but for most users it's irrelevant. If you've got a disk that uses a technology that works best with a power-of-2 4 KiB to 1 MiB alignment, you must examine the start sector (not the starting or ending cylinder) and determine if the value is divisible by the appropriate number.
:-s
you lost me a little, but i think you said its mostly irrelevant today, my pc is not even a year old yet. very informative reply though