Date: Tue, 21 Apr 1998 02:05:03 +1000 From: Bruce Evans <bde@zeta.org.au> To: bde@zeta.org.au, mike@smith.net.au Cc: dburr@POBoxes.com, hardware@FreeBSD.ORG, stable@FreeBSD.ORG, Studded@san.rr.com Subject: Re: best wdc0 flags ? Message-ID: <199804201605.CAA04114@godzilla.zeta.org.au>
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>> > I tried those flags and noticed that it turned on 32-bit transfers for >> >my wd0, resulting in a 20% increase in throughput. Out of curiosity, why >> >aren't these flags included in GENERIC? >> >> Becuase they break operation of drives that don't support them. > >Do we have any examples of controllers that don't? I thought I did, but my oldest accessible drive (all 400MB of it from 4 years ago) supports them. The probe seems to handle any that don't. Setting the multi-block flag is not such a good optimization, since it pessimizes throughput on some drives and it increases interrupt latency. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message
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