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Message-ID: <4753F37F.6050105@marquesminen.com.ar>
Date: Mon, 03 Dec 2007 09:15:59 -0300
From: Martin Marques <martin@marquesminen.com.ar>
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To: Greg Smith <gsmith@gregsmith.com>
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Subject: Re: full_page_writes = off?
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Greg Smith escribió:
> On Sat, 1 Dec 2007, Tomasz Ostrowski wrote:
> 
>> You can also use "hdparm -I" to check this - look for a "Write
>> caching" in "Commands/features" section. If it has a "*" in front
>> then it is enabled and dangerous.
> 
> Right; using -I works with most Linux hdparm versions:
> 
> # hdparm -V
> hdparm v6.6
> # hdparm -I /dev/hda | grep "Write cache"
>            *    Write cache
> # hdparm -W 0 /dev/hda
> 
> /dev/hda:
>  setting drive write-caching to 0 (off)
> # hdparm -I /dev/hda | grep "Write cache"
>                 Write cache

Out of ignorance, do RAID[1] devices have write cache?

[1]: I'm talking about RAID through hardware.