gmirror using two 500GB WD RE3:
Code:
ad4: 476940MB <WDC WD5002ABYS-01B1B0 02.03B02> at ata2-master SATA300
ad6: 476940MB <WDC WD5002ABYS-01B1B0 02.03B02> at ata3-master SATA300
These times are not 100% accurate since this disks are being used while testing (Not too heavily though).
Huge difference in seek times vs. your 640GB WD drive vermaden ...
Code:
[~]# diskinfo -c -t /dev/mirror/datad
/dev/mirror/datad
512 # sectorsize
500107853312 # mediasize in bytes (466G)
976773151 # mediasize in sectors
I/O command overhead:
time to read 10MB block 0.126509 sec = 0.006 msec/sector
time to read 20480 sectors 2.599029 sec = 0.127 msec/sector
calculated command overhead = 0.121 msec/sector
Seek times:
Full stroke: 250 iter in 1.269161 sec = 5.077 msec
Half stroke: 250 iter in 1.257387 sec = 5.030 msec
Quarter stroke: 500 iter in 2.042965 sec = 4.086 msec
Short forward: 400 iter in 1.785337 sec = 4.463 msec
Short backward: 400 iter in 2.027775 sec = 5.069 msec
Seq outer: 2048 iter in 0.349996 sec = 0.171 msec
Seq inner: 2048 iter in 0.315424 sec = 0.154 msec
Transfer rates:
outside: 102400 kbytes in 0.994393 sec = 102977 kbytes/sec
middle: 102400 kbytes in 1.153631 sec = 88763 kbytes/sec
inside: 102400 kbytes in 1.708459 sec = 59937 kbytes/sec