[COMMITTERS] pgsql: Reduce the number of pallocs() in BRIN

Reduce the number of pallocs() in BRIN

Instead of allocating memory in brin_deform_tuple and brin_copy_tuple
over and over during a scan, allow reuse of previously allocated memory.
This is said to make for a measurable performance improvement.

Author: Jinyu Zhang, Álvaro Herrera
Reviewed by: Tomas Vondra
Discussion: https://postgr.es/m/495deb78.4186.1500dacaa63.Coremail.beijing_pg@163.com

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/8bf74967dab1b368f4e217c960ede1516c42a989

Modified Files
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contrib/pageinspect/brinfuncs.c        |  3 +-
src/backend/access/brin/brin.c         | 24 +++++++----
src/backend/access/brin/brin_pageops.c |  4 +-
src/backend/access/brin/brin_tuple.c   | 77 +++++++++++++++++++++-------------
src/include/access/brin_tuple.h        | 12 ++++--
5 files changed, 78 insertions(+), 42 deletions(-)