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Date: Fri, 27 Sep 2002 09:45:09 +0200
From: Jens Axboe <axboe@suse.de>
To: Matthew Jacob <mjacob@feral.com>
Cc: "Justin T. Gibbs" <gibbs@scsiguy.com>,
       "Pedro M. Rodrigues" <pmanuel@myrealbox.com>,
       Mathieu Chouquet-Stringer <mathieu@newview.com>,
       linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Warning - running *really* short on DMA buffers while doing file transfers
Message-ID: <20020927074509.GA860@suse.de>
References: <Pine.BSF.4.21.0209270029280.18144-100000@beppo> <Pine.BSF.4.21.0209270031360.18144-100000@beppo>
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On Fri, Sep 27 2002, Matthew Jacob wrote:
> 
> The issue here is not whether it's appropriate to oversaturate the
> 'standard' SCSI drive- it isn't- I never suggested it was.

Ok so we agree. I think our oversaturate thresholds are different,
though.

> I'd just suggest that it's asinine to criticise an HBA for running up to
> reasonable limits when it's the non-toy OS that will do sensible I/O
> scheduling. So point your gums elsewhere.

Well I don't think 253 is a reasonable limit, that was the whole point.
How can sane io scheduling ever prevent starvation in that case? I can't
point my gums elsewhere, this is where I'm seeing starvation.

-- 
Jens Axboe