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Old 6th July 2009
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Carpetsmoker Carpetsmoker is offline
Real Name: Martin
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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
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