more consistent order for views_lk / schema_lk / bdb lock ordering #5993
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dorinhogea wants to merge 1 commit into
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more consistent order for views_lk / schema_lk / bdb lock ordering #5993dorinhogea wants to merge 1 commit into
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…K ordering in time partition paths. 1. views_cron_restart (db/views.c): BDB_READLOCK was acquired AFTER views_lk, inverting the order of tpt rollout code. While a deadlock is not possible, it is cleaner and more consistent. 2. _view_cron_phase2 (db/views.c): BDB_READLOCK was acquired mid-function after both schema_lk and views_lk were already held. 3. toblock.c: views_lk(rd) is acquired before schema_lk(wr) is taken deep inside bplog_schemachange_run(); we block any transaction that contains both a tpt bptran and another ddl; this prevents a deadlock from happening; fixing the order requires more complicated refactoring. Signed-off-by: dhogea <dhogea@bloomberg.net>
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May 30, 2026
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Cbuild submission: Success ✓.
Regression testing: Success ✓.
The first 10 failing tests are:
logfill [db unavailable at finish] **quarantined**
sc_resume_logicalsc_generated **quarantined**
sp_snapshot_generated
consumer_non_atomic_default_consumer_generated **quarantined**
remotecreate_twopc_generated
remotecreate
sc_downgrade [timeout] **quarantined**
truncatesc_offline_generated [timeout] **quarantined**
reco-ddlk-sql [timeout] **quarantined**
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views_cron_restart (db/views.c): BDB_READLOCK was acquired AFTER views_lk, inverting the order of tpt rollout code. While a deadlock is not possible, it is cleaner and more consistent.
_view_cron_phase2 (db/views.c): BDB_READLOCK was acquired mid-function after both schema_lk and views_lk were already held.
toblock.c: views_lk(rd) is acquired before schema_lk(wr) is taken deep inside bplog_schemachange_run(); we block any transaction that contains both a tpt bptran and another ddl; this prevents a deadlock from happening; fixing the order requires more complicated refactoring.