|
84 | 84 | # Test that interruption of DROP DATABASE is handled properly. To ensure the |
85 | 85 | # interruption happens at the appropriate moment, we lock pg_tablespace. DROP |
86 | 86 | # DATABASE scans pg_tablespace once it has reached the "irreversible" part of |
87 | | -# dropping the database, making it a suitable point to wait. |
| 87 | +# dropping the database, making it a suitable point to wait. Since relcache |
| 88 | +# init reads pg_tablespace, establish each connection before locking. This |
| 89 | +# avoids a connection-time hang with debug_discard_caches. |
| 90 | +my$cancel =$node->background_psql('postgres',on_error_stop=> 1); |
88 | 91 | my$bgpsql =$node->background_psql('postgres',on_error_stop=> 0); |
89 | 92 | my$pid =$bgpsql->query('SELECT pg_backend_pid()'); |
90 | 93 |
|
|
100 | 103 | # Try to drop. This will wait due to the still held lock. |
101 | 104 | $bgpsql->query_until(qr//,"DROP DATABASE regression_invalid_interrupt;\n"); |
102 | 105 |
|
103 | | -# Ensure we're waiting for the lock |
104 | | -$node->poll_query_until('postgres', |
105 | | -qq(SELECT EXISTS(SELECT * FROM pg_locks WHERE NOT granted AND relation = 'pg_tablespace'::regclass AND mode = 'AccessShareLock');) |
106 | | -); |
107 | 106 |
|
108 | | -# and finally interrupt the DROP DATABASE |
109 | | -ok($node->safe_psql('postgres',"SELECT pg_cancel_backend($pid)"), |
| 107 | +# Once the DROP DATABASE is waiting for the lock, interrupt it. |
| 108 | +ok($cancel->query_safe( |
| 109 | +qq( |
| 110 | +DO\$\$ |
| 111 | +BEGIN |
| 112 | +WHILE NOT EXISTS(SELECT * FROM pg_locks WHERE NOT granted AND relation = 'pg_tablespace'::regclass AND mode = 'AccessShareLock') LOOP |
| 113 | +PERFORM pg_sleep(.1); |
| 114 | +END LOOP; |
| 115 | +END\$\$; |
| 116 | +SELECT pg_cancel_backend($pid);)), |
110 | 117 | "canceling DROP DATABASE"); |
| 118 | +$cancel->quit(); |
111 | 119 |
|
112 | 120 | # wait for cancellation to be processed |
113 | 121 | ok( pump_until( |
|
116 | 124 | "cancel processed"); |
117 | 125 | $bgpsql->{stderr} =''; |
118 | 126 |
|
119 | | -# verify that connection to the database aren't allowed |
| 127 | +# Verify that connections to the database aren't allowed. The backend checks |
| 128 | +# this before relcache init, so the lock won't interfere. |
120 | 129 | is($node->psql('regression_invalid_interrupt',''), |
121 | 130 | 2,"can't connect to invalid_interrupt database"); |
122 | 131 |
|
|