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Date:   Mon, 7 Dec 2020 18:26:03 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Greg KH <greg@kroah.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Daejun Park <daejun7.park@samsung.com>,
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        "asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
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        "stanley.chu@mediatek.com" <stanley.chu@mediatek.com>,
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        "bvanassche@acm.org" <bvanassche@acm.org>,
        "tomas.winkler@intel.com" <tomas.winkler@intel.com>,
        ALIM AKHTAR <alim.akhtar@samsung.com>,
        "gregkh@google.com" <gregkh@google.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Sang-yoon Oh <sangyoon.oh@samsung.com>,
        Sung-Jun Park <sungjun07.park@samsung.com>,
        yongmyung lee <ymhungry.lee@samsung.com>,
        Jinyoung CHOI <j-young.choi@samsung.com>,
        Adel Choi <adel.choi@samsung.com>,
        BoRam Shin <boram.shin@samsung.com>,
        SEUNGUK SHIN <seunguk.shin@samsung.com>
Subject: Re: [PATCH v13 0/3] scsi: ufs: Add Host Performance Booster Support
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On Mon, Dec 07, 2020 at 07:23:12PM +0100, Greg KH wrote:
> What "real workload" test can be run on this to help show if it is
> useful or not?  These vendors seem to think it helps for some reason,
> otherwise they wouldn't have added it to their silicon :)
> 
> Should they run fio?  If so, any hints on a config that would be good to
> show any performance increases?

A real actual workload that matters.  Then again that was Martins
request to even justify it.  I don't think the broken addressing that
breaks a whole in the SCSI addressing has absolutely not business being
supported in Linux ever.  The vendors should have thought about the
design before committing transistors to something that fundamentally
does not make sense.