The Western Digital Advanced Format Performance Comparison Guide

Nice review as always. Did you align the partitions on that drive when you did your tests or was it completely unpartitioned?

Here is the proper way to align the partitions with these Advance Format drives under Linux (dunno how to do it under windows). I own a WD20EARS by the way.

Used fdisk (setting both modes 'c' and 'u') and align it to sector 2048 - interestingly, in sector mode, the default starting point is not 63 or 64 but 2048 in the current version of fdisk (2.17.2) so it's automatically taking care of the 4k sector size for me. Everything works fast so I'm assuming that it's correct.

Credit to this post.

Here are some reference numbers on three drives:

a = Seagate 7200.12 ST31000528AS (1.0 TB) spinning at 7200 RPM
b = WD Black WD1001FALS (1.0 TB) spinning at 7200 RPM
c = WD Green WD20EARS (2.0 TB) spinning at 5900 RPM

Code:

# hdparm -Tt /dev/sd[a-c]

/dev/sda:
 Timing cached reads:   15512 MB in  1.99 seconds = 7780.21 MB/sec
 Timing buffered disk reads:  338 MB in  3.02 seconds = 112.07 MB/sec

/dev/sdb:
 Timing cached reads:   15796 MB in  1.99 seconds = 7922.77 MB/sec
 Timing buffered disk reads:  308 MB in  3.01 seconds = 102.20 MB/sec

/dev/sdc:
 Timing cached reads:   15128 MB in  1.99 seconds = 7586.77 MB/sec
 Timing buffered disk reads:  356 MB in  3.01 seconds = 118.08 MB/sec

Not too bad considering the WD20EARS spins ~18 % slower than the other two.

NOTW: This drive also attempts to park the read heads once every 8 seconds which is just horrible. Use hdparm in your /etc/rc.local to disable this 'feature' and likely add life to your hdd:

Code:

# echo "hdparm -S 242 /dev/sdX" > /etc/rc.local

Use the following bash script I wrote to detect the presence of this drive on your system in case you use it periodically as I do as a backup drive and automatically send that hdparm command. Note that I only have a single WD20EARS on my system - this script won't work for multiple copies.

Code:

#!/bin/bash
test=`fdisk -l | grep 2000.4 | cut -c13-13`
if [ -z "$test" ]; then
 echo retarded drive not found, exiting
 exit 0
else
 echo retarded drive found, fixing lcc
 hdparm -S 242 /dev/sd$test
fi