quans...@quanstro.net:
> word 106 6003 [valid=1]
> multiple log/phys? 1
> log/phys 8
> logical sector size 0 [valid=0]
On my WD10EARS, word 106 of the ATA identify block is 0, indicating
no support for logical sectors.
I've just tried the experiment of creating eight 1GB partitions
aligned at each possible logical sector offset, and found that
alignment doesn't seem to affect the writing speed significantly:
term% awk '/test/ {print $0,"align " $3 % 8}' /dev/sdC0/ctl
part test0 28249856 30249856 align 0
part test1 30249857 32249857 align 1
part test2 32249858 34249858 align 2
part test3 34249859 36249859 align 3
part test4 36249860 38249860 align 4
part test5 38249861 40249861 align 5
part test6 40249862 42249862 align 6
part test7 42249863 44249863 align 7
term% for (i in /dev/sdC0/test?) { time rc -c 'dd -if /dev/zero -of '$i' -bs 4k
-count 250000 >[2]/dev/null' }
0.57u 8.43s 20.40r rc -c dd -if /dev/zero -of /dev/sdC0/test0 -bs 4k
-count 250000 >[2]/dev/null
0.50u 8.65s 20.71r rc -c dd -if /dev/zero -of /dev/sdC0/test1 -bs 4k
-count 250000 >[2]/dev/null
0.64u 8.44s 20.73r rc -c dd -if /dev/zero -of /dev/sdC0/test2 -bs 4k
-count 250000 >[2]/dev/null
0.60u 8.86s 20.54r rc -c dd -if /dev/zero -of /dev/sdC0/test3 -bs 4k
-count 250000 >[2]/dev/null
0.64u 8.70s 20.77r rc -c dd -if /dev/zero -of /dev/sdC0/test4 -bs 4k
-count 250000 >[2]/dev/null
0.55u 9.00s 20.62r rc -c dd -if /dev/zero -of /dev/sdC0/test5 -bs 4k
-count 250000 >[2]/dev/null
0.48u 8.51s 20.61r rc -c dd -if /dev/zero -of /dev/sdC0/test6 -bs 4k
-count 250000 >[2]/dev/null
0.59u 8.16s 20.78r rc -c dd -if /dev/zero -of /dev/sdC0/test7 -bs 4k
-count 250000 >[2]/dev/null
This all seems to contradict WD's claim (*) that the WD10EARS is an
advanced format drive.
(*) http://www.wdc.com/wdproducts/library/SpecSheet/ENG/2879-701229.pdf
