Fdisk shows logical sector size smaller than physical sector size after clonezilla

narnie · 02-08-2013, 12:56 AM

I bought a new 1tb HD adding it to a 750gb drive. I have a duel boot Windows/Linux Mint Debian setup. I did a clonezilla to copy the 750gb drive to the 1tb drive (it used partclone, I believe).

I did an fdisk /dev/sdb (the newer 1tb drive) to examine the drive. It showed this error:

Quote:

The device presents a logical sector size that is smaller than the physical sector size. Aligning to a physical sector size boundary is recommended or performance may be impacted.

Code:

$ /sbin/fdisk -v
fdisk (util-linux 2.20.1)

Is this a real problem, or is this an fdisk version issue? If it is a real issue, how do I deal with it? Esp with copying over the Windows recovery partition and windows partitions?

I am also wondering about design issues. I would prefer Windows os on the original and my Windows data (user data, etc) on the new drive and the reverse for my Linux, but how hard is it to switch a Windows data volume to another disk (it is already copied onto that disk). The easier road I think would just be let /dev/sda be for Windows and /dev/sdb be for linux, but performance would be better the other way. Thoughts?

Thanks,
Narnie

TobiSGD · 02-08-2013, 05:10 AM

This is a real problem. Some newer drives (and it will be more in the future) use physical sector sizes of 4KB instead of the older 512B. In order to get full write performance from the disk partitions have to be aligned to those physical sectors. So make sure that the startsector of any partition can be divided by 8.

narnie · 02-08-2013, 03:20 PM

Quote:

Originally Posted by TobiSGD

This is a real problem. Some newer drives (and it will be more in the future) use physical sector sizes of 4KB instead of the older 512B. In order to get full write performance from the disk partitions have to be aligned to those physical sectors. So make sure that the startsector of any partition can be divided by 8.

OK, I wiped the drive and reformated it with SystemRescueCD using gparted mimicking my old HD's partition scheme/sizes. I checked the first sector of each partition and they are all divisible by 8. However, when I do a fdisk, I still get the fdisk warning. Is that OK or should that warning have gone away if my startsector for each partition is divisible by 8 and everything is ok to copy over and put it into production?

Thanks,
Narnie

rknichols · 02-08-2013, 08:32 PM

If you would post the output from "fdisk -lu" for that drive, someone could give a definitive answer.

narnie · 02-09-2013, 06:02 PM

Quote:

Originally Posted by rknichols

If you would post the output from "fdisk -lu" for that drive, someone could give a definitive answer.

Here 'tis.

Code:

# fdisk -lu /dev/sdb

Disk /dev/sdb: 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: 0x00011318

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048       86015       41984    6  FAT16
/dev/sdb2           86016    30801919    15357952    7  HPFS/NTFS/exFAT
/dev/sdb3   *    30801920   212738047    90968064    7  HPFS/NTFS/exFAT
/dev/sdb4       212738048  1953523711   870392832    5  Extended
/dev/sdb5       212740096   422453247   104856576    7  HPFS/NTFS/exFAT
/dev/sdb6       422455296   527312895    52428800   83  Linux
/dev/sdb7       527314944  1940940799   706812928   83  Linux
/dev/sdb8      1940942848  1953523711     6290432   82  Linux swap / Solaris

Thank you for any help.

Narnie

rknichols · 02-09-2013, 09:56 PM

That all looks like it should be just fine.