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Date: Thu, 26 Feb 2009 07:28:12 +0100 (CET)
From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Josh Paetzel <josh@tcbug.org>
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Cc: questions@freebsd.org
Subject: Re: SAS drives seem slow
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> FreeBSD services.tcbug.org 8.0-CURRENT FreeBSD 8.0-CURRENT #0: Mon Feb 16 
> 21:07:14 UTC 2009     root@:/usr/obj/usr/src/sys/SERVICES  amd64
>
> But 6.x and 7.x give similar results.
>
> The disks themselves are capable of sequential read/write in the 180 Meg/sec 
> range, so I'm trying to understand why I'm being told they are 100 Meg/sec, 
> and why that seems to be their real world performance cap.
>

probably you use RAID5

> # dd if=/dev/zero of=stuff bs=8m count=100
> 100+0 records in
> 100+0 records out
> 838860800 bytes transferred in 8.711125 secs (96297644 bytes/sec)
>
> Thanks,
>
> Josh Paetzel
>
>
>
>
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