Re: Alignment of disk-I/O from userland.

From: Bruce M Simpson (bms_at_spc.org)
Date: 10/07/03

  • Next message: Poul-Henning Kamp: "Re: Alignment of disk-I/O from userland." 
    Date: Tue, 7 Oct 2003 17:02:31 +0100
To: Ben Mesander <ben@timing.com>

    On Tue, Oct 07, 2003 at 09:41:17AM -0600, Ben Mesander wrote:
    > How about a flag for open(2), such as O_DIRECT, which would indicate
    > if the fd in question is such a device, and you did not sufficiently
    > align, etc. your buffers, then you get an error when you attempt the
    > I/O operation.

    O_DIRECT is already used to indicate that the application wishes to bypass
    the buffer cache.

    I think Scott's proposal, that the busdma API gets re-used, creating bounce
    buffers where necessary, makes sense.

    I think that if phk intends to 'raise the bar', he'd better be buying the
    drinks at EuroBSDCon. :-)

    BMS
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  • Next message: Poul-Henning Kamp: "Re: Alignment of disk-I/O from userland."

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