pgsql: Update: < multiple I/O channels simultaneously.

Log Message:
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Update:

< multiple I/O channels simultaneously.

multiple I/O channels simultaneously. One idea is to create a
background reader that can pre-fetch sequential and index scan
pages needed by other backends. This could be expanded to allow
concurrent reads from multiple devices in a partitioned table.

Modified Files:
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pgsql/doc:
TODO (r1.1793 -> r1.1794)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1793&amp;r2=1.1794)
pgsql/doc/src/FAQ:
TODO.html (r1.297 -> r1.298)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/FAQ/TODO.html.diff?r1=1.297&amp;r2=1.298)