Date: Wed, 15 Dec 1999 14:23:53 -0800 (PST) From: Ian Struble <ian@broken.net> To: Jonathon McKitrick <jcm@dogma.freebsd-uk.eu.org> Cc: chris reaume <chris@saturn.aepnet.com>, freebsd-questions@FreeBSD.ORG Subject: Re: vaio's.. Message-ID: <Pine.BSF.3.91.991215140625.23637F-100000@disavowed.broken.net> In-Reply-To: <Pine.BSF.4.21.9912152128560.95432-100000@dogma.freebsd-uk.eu.org>
next in thread | previous in thread | raw e-mail | index | archive | help
> On Tue, 14 Dec 1999, chris reaume wrote: > >I got my raw disk throughput (as measured by dd <shrug>) up from 3mb/s to > >12 by adding flags 0xa0ffa0ff to my controller wdc0 line in my kernel > >config file: > >controller wdc0 at isa? port "IO_WD1" bio irq 14 flags 0xa0ffa0ff > > Does this only work for certain HDs? (Pardon my ignorance) There has to > be a catch somewhere, right? Well yes of course it does vary from HD to HD but probably not as much as you would think. The flags mentioned do two things(two both the master and the slave on the controller). The 'a'(8+2+1) is a combination of a few flag for enabling 32bit disk access, DMA and LBA for disk transfers. The 'ff' indicates the max number of i/o buffers that can be read/written at once. If this is a really bad summary of what is really going on, someone please correct me and/or present it in a little clearer manner. Thanks! If you really want to know what the flags mean you can check on then in /usr/src/sys/i386/isa/wd.c. But in the meantime here is the relivant code: #define WDOPT_32BIT 0x8000 #define WDOPT_SLEEPHACK 0x4000 #define WDOPT_DMA 0x2000 #define WDOPT_LBA 0x1000 #define WDOPT_FORCEHD(x) (((x)&0x0f00)>>8) #define WDOPT_MULTIMASK 0x00ff Ian To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.3.91.991215140625.23637F-100000>