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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Dieter BSD <dieterbsd@gmail.com>
Subject: Re: IBM blade server abysmal disk write performances
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>
> Note that the driver says "Command Queueing enabled" without
> specifying which.  If the driver is trying to use SATA's NCQ but
> the drive only speaks SCSI's TCQ, that could explain it. Or if
> the TCQ isn't working for some other reason.

even without TCQ,NCQ and write cache the write speed is really terrible.