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Message-ID: <e00686432d2aa09880f801eecadbb2bdf6d23573.camel@gmail.com>
Subject: Re: [PATCH v2] scsi: ufs: Allow RTT negotiation
From: Bean Huo <huobean@gmail.com>
To: Avri Altman <avri.altman@wdc.com>, "Martin K . Petersen"
	 <martin.petersen@oracle.com>
Cc: Bart Van Assche <bvanassche@acm.org>, Bean Huo <beanhuo@micron.com>, 
	linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Date: Wed, 08 May 2024 18:32:40 +0200
In-Reply-To: <20240503113429.7220-1-avri.altman@wdc.com>
References: <20240503113429.7220-1-avri.altman@wdc.com>
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On Fri, 2024-05-03 at 14:34 +0300, Avri Altman wrote:
> UFS4.0, and specifically gear 5 changes this, and requires the device
> to
> be more attentive.=C2=A0 This doesn't come free - the device has to
> allocate
> more resources to that end, but the sequential write performance
> improvement is significant. Early measurements shows 25% gain when
> moving from rtt 2 to 9. Therefore, set bMaxNumOfRTT to be
> min(bDeviceRTTCap, NORTT) as UFSHCI expects.
>=20
> Signed-off-by: Avri Altman <avri.altman@wdc.com>


Avri,

I was still curious about this 25% gain, so I will take a look. It
would be great if you could share more information about this.


Reviewed-by: Bean Huo <beanhuo@micron.com>