pgsql: Wake up launcher when enabling a subscription

Wake up launcher when enabling a subscription

Otherwise one would have to wait up to DEFAULT_NAPTIME_PER_CYCLE until
the subscription worker is considered for starting.

There is a small race condition: If one enables a subscription right
after disabling it, the launcher might not have registered the stopping
when receiving the wakeup signal for the re-enabling. The start will
then not happen right away but after the full cycle time.

Author: Kyotaro HORIGUCHI <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a3f17b9c315512e9c116dbc243056aad8b372e18

Modified Files
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src/backend/commands/subscriptioncmds.c | 3 +++
1 file changed, 3 insertions(+)