pgsql: Make GIN's cleanup pending list process interruptable

Make GIN's cleanup pending list process interruptable

Cleanup process could be called by ordinary insert/update and could take a lot
of time. Add vacuum_delay_point() to make this process interruptable. Under
vacuum this call will also throttle a vacuum process to decrease system load,
called from insert/update it will not throttle, and that reduces a latency.

Backpatch for all supported branches.

Jeff Janes <jeff(dot)janes(at)gmail(dot)com>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e26692248ada18417199b47bc2e4e1648d530953

Modified Files
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src/backend/access/gin/ginfast.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)