Обсуждение: pgsql: pg_upgrade: document use of rsync for slave upgrades

pg_upgrade: document use of rsync for slave upgrades

Also document that rsync has one-second granularity for file
change comparisons.

Report by Stephen Frost

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/417f78a5178815d8c10f86b1561c88c45c53c2d2

Modified Files
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doc/src/sgml/backup.sgml    |    6 +-
doc/src/sgml/pgupgrade.sgml |  159 ++++++++++++++++++++++++++++++++++++++++---
2 files changed, 152 insertions(+), 13 deletions(-)