hard drive performance

[Ivan Voras]

Alexander Best wrote:
> hi there,
> 
> i have 2 hard drives running. the first one is SATA300 and the other one
> UDMA100. here are the dmesg entries:
> 
> ad0: 238474MB <SAMSUNG SP2504C VT100-50> at ata0-master SATA300
> ad1: 157066MB <Hitachi HDS722516VLAT80 V34OA63A> at ata4-master UDMA100
> 
> i've tried to test the drives' performances using the following commands:
> 
> dd if=/dev/ad0 of=/dev/null bs=1m count=300
> and
> dd if=/dev/ad1 of=/dev/null bs=1m count=300
> 
> the results are:
> ad0 = 314572800 bytes transferred in 4.325645 secs (72722751 bytes/sec)
> ad1 = 314572800 bytes transferred in 5.166126 secs (60891430 bytes/sec)
> 
> the results for ad0 are a bit disappointing though. is this normal or is bs=1m
> wrong?

70+ MB/s is a perfectly fine speed for a modern drive. The "300" in
SATA300 doesn't mean what you probably think it means.

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