Re: [pgsql-patches] O_DIRECT support for Windows

I've done some further looking aruond at this, and I've been unable to find
any references to disk systems with sector size > 8192 bytes (which is what
the alignment of the buffers per XLOG_BLCKSZ, at leastby default).

So I'll commit this fairly simple patch, and we'll revert it or add runtime
checks later if we find out that there exist such systems somewhere..

//Magnus


On Mon, Apr 02, 2007 at 04:39:00PM -0400, Bruce Momjian wrote:
>
> Your patch has been added to the PostgreSQL unapplied patches list at:
>
>     http://momjian.postgresql.org/cgi-bin/pgpatches
>
> It will be applied as soon as one of the PostgreSQL committers reviews
> and approves it.
>
> ---------------------------------------------------------------------------
>
>
> ITAGAKI Takahiro wrote:
> > The attached is a patch to define O_DIRECT by ourselves on Windows,
> > and to map O_DIRECT to FILE_FLAG_NO_BUFFERING.
> >
> > There will be a consistency in our support between Windows and other OSes
> > that have O_DIRECT. Also, there is the following comment that says, I read,
> > we should do so.
> > | handle other flags? (eg FILE_FLAG_NO_BUFFERING/FILE_FLAG_WRITE_THROUGH)
> >
> > Is this worth doing? Do we need more performance reports for the change?
> >
> > Regards,
> > ---
> > ITAGAKI Takahiro
> > NTT Open Source Software Center
>
> [ Attachment, skipping... ]
>
> >
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> --
>   Bruce Momjian  <bruce@momjian.us>          http://momjian.us
>   EnterpriseDB                               http://www.enterprisedb.com
>
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