G
George Potemkin
Guest
Quick test results: 1. If we just create a CDC policy for a table then the /reading/ its records will cause OM latch activity. But only if you don't restart a database. 2. The number of OM latch locks is increasing with the record reads. For example, 1 read -> 2 OM latch locks, 10 reads -> 600+ OM latch locks. 3. OM latch activity stays the same even if you delete a CDC policy. Unless you restart a database. 4. 'FOR EACH _Cdc-Table-Policy NO-LOCK' query caused the OM latch locks in production. Really a session running CDCAdminProcess.p crashed while holding the OM latch: ABL 1507: (49) SYSTEM ERROR: Memory violation. WDOG 1507: (5028) SYSTEM ERROR: Releasing regular latch. latchId: 3 But the tests show no OM latch locks when the query reads one record in _Cdc-Table-Policy.
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