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Re: Unix filesystem: use buffered IO or direct IO?

From: Yong Huang <yong321_at_yahoo.com>
Date: 25 Apr 2002 15:12:53 -0700
Message-ID: <b3cb12d6.0204251412.64ec8161@posting.google.com>


Isn't sequential read sequential, like in the case of index scan (full or range)? Isn't reading TEMP direct path read, bypassing Oracle buffer cache?

Full table scans are usually db file scattered read, scattered at the OS level.

Yong Huang
yong321_at_yahoo.com

Michael Brown <mlbrown_at_apps-dba.net> wrote in message news:<qq4bcusa3bos2nr0ichgl6sm5uher4i5u3_at_4ax.com>...
> db file sequential read is either random single block reads or
> transfers from the TEMP tablespace during a sort. The TEMP tablespace
> I/O might benefit from buffering, but odds are the random single block
> reads won't see any benefit from system buffers assuming that your
Received on Thu Apr 25 2002 - 17:12:53 CDT

Original text of this message

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