pgsql: Allocate all page images at once in generic wal interface

Allocate all page images at once in generic wal interface

That reduces number of allocation.

Per gripe from Michael Paquier and Tom Lane suggestion.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/7c979c95a3700d0bd34c2831f49a9260d505b0f9

Modified Files
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src/backend/access/transam/generic_xlog.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)