pgsql: Clear 'xid' in dummy async notify entries written to fill up pag

Clear 'xid' in dummy async notify entries written to fill up pages

Before we started to freeze async notify entries (commit 8eeb4a0f7c),
no one looked at the 'xid' on an entry with invalid 'dboid'. But now
we might actually need to freeze it later. Initialize them with
InvalidTransactionId to begin with, to avoid that work later.

Álvaro pointed this out in review of commit 8eeb4a0f7c, but I forgot
to include this change there.

Author: Álvaro Herrera <alvherre(at)kurilemu(dot)de>
Discussion: https://www.postgresql.org/message-id/202511071410.52ll56eyixx7@alvherre.pgsql
Backpatch-through: 14

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0bdc777e80071abd77674f1e66258d410a010aa9

Modified Files
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src/backend/commands/async.c | 1 +
1 file changed, 1 insertion(+)