pgsql: Limit pg_basebackup progress output to 1/second

Limit pg_basebackup progress output to 1/second

This prevents pg_basebackup from generating excessive output when
dumping large clusters. The status is now updated once / second,
still making it possible to see that there is progress happening,
but limiting the total bandwidth.

Mika Eloranta, reviewed by Sawada Masahiko and Oskari Saarenmaa

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/8198a321c9ea2072c5acde438f4d19638e04f6f2

Modified Files
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src/bin/pg_basebackup/pg_basebackup.c | 35 +++++++++++++++++++++++----------
1 file changed, 25 insertions(+), 10 deletions(-)