RE: Oracle on Windows Vs. Linux

From: Kevin Closson <kevinc_at_polyserve.com>
Date: Fri, 19 May 2006 22:28:32 -0700
Message-ID: <5D2570CAFC98974F9B6A759D1C74BAD0E5A4C5@ex2.ms.polyserve.com>

 >>>> 

>>>> set filesystemio_options = directIO and atime will not be
>>>> updated...that is opne of the by-products of open with the
>>>O_DIRECT
>>>> flag.
>>>
>>>Yes but directio doesn't necessarily make Oracle IO faster.
>>>A little bit more is needed. aio is a better bet.

..oh, async ? really? silly me.

The post you are responding to had to do with Jared's point about atime updates. Async or not, direct I/O is what circumvents mtime/atime updates.

BTW, neither direct, nor async make I/O "faster". The DMA transfer takes as long as the I/O subsystem will facilitate. However, direct and/or async usually handles the same amount of I/O with improved processor efficiency...and that, generally improves overall system throughput. Oracle Disk Manager is about the most efficient I/O library for Oracle...should be, Oracle defined the library...but I digress.

I'm flashing back now..uh, right, it was 6.0.27 on Sequent DYNIX/ptx where we implemented direct+async I/O on filesystem files for the first time... ah, the good old days

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Received on Sat May 20 2006 - 00:28:32 CDT