4
votes
1answer
2k views

How would I force Debian to use the physical sector size on a hard disk?

I just purchased a few new 3TB WD drives. These have physical 4k sectors, but there is some sort of layer which is providing 512B logical sectors (see the partition table below). In order to attempt ...
1
vote
3answers
1k views

logical sector size changes depending on whether it is attached via USB or direct SATA

I have a 3TB WD disk (in a My Book Essential external drive.) I used parted under Linux to partition it with a GPT disklabel and loaded it up with data from my laptop through the USB cable. Then I ...
0
votes
2answers
476 views

Why is my magnetic hard drive exceedingly slow?

Writes to my WD Caviar Green 2TB hard drive are exceedingly slow. When dpkg is setting up packages atop reports speeds of between 0.5 and 1 MB/s. AHCI is enabled in my bios. I bought the drive new. ...
7
votes
2answers
659 views

How do I test to see if all writes to my hard drive are aligned to its 4k sectors?

I'm using Linux with 4 hard drives that use 4k sectors. There are several layers between my filesystem and the raw devices: Disks > Linux Raid 5 > dm-crypt > LVM. Every resource I have found has ...
1
vote
1answer
3k views

Performance of RAID 5 with mdadm

I have set up a software-raid 5 with mdadm on a 1.3 GHz AMD Neo 36L dual core machine using 3 1.5 TB Seagate Barracude Green drives (4k sectors). The chunk size of the raid is 512 KB. On top of the ...
6
votes
2answers
5k views

Is my OCZ SSD aligned correctly?

I have an OCZ Agility 2 SSD with 40 GB of space. I use it as a system drive in Debian Linux ("Squeeze") and in my opinion it's really fast. I've read a lot on aligning partitions and file systems, and ...