1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
|
Parsed test spec with 2 sessions
starting permutation: lock assign1 vacuum unlock
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
step lock:
SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
(1 row)
step assign1:
do $$
declare
x text;
begin
select test1.b into x from test1;
delete from test1;
commit;
perform pg_advisory_lock(1);
raise notice 'length(x) = %', length(x);
end;
$$;
<waiting ...>
step vacuum:
VACUUM test1;
step unlock:
SELECT pg_advisory_unlock(1);
pg_advisory_unlock
------------------
t
(1 row)
s1: NOTICE: length(x) = 6000
step assign1: <... completed>
starting permutation: lock assign2 vacuum unlock
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
step lock:
SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
(1 row)
step assign2:
do $$
declare
x text;
begin
x := (select test1.b from test1);
delete from test1;
commit;
perform pg_advisory_lock(1);
raise notice 'length(x) = %', length(x);
end;
$$;
<waiting ...>
step vacuum:
VACUUM test1;
step unlock:
SELECT pg_advisory_unlock(1);
pg_advisory_unlock
------------------
t
(1 row)
s1: NOTICE: length(x) = 6000
step assign2: <... completed>
starting permutation: lock assign3 vacuum unlock
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
step lock:
SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
(1 row)
step assign3:
do $$
declare
r record;
begin
select * into r from test1;
r.b := (select test1.b from test1);
delete from test1;
commit;
perform pg_advisory_lock(1);
raise notice 'length(r) = %', length(r::text);
end;
$$;
<waiting ...>
step vacuum:
VACUUM test1;
step unlock:
SELECT pg_advisory_unlock(1);
pg_advisory_unlock
------------------
t
(1 row)
s1: NOTICE: length(r) = 6004
step assign3: <... completed>
starting permutation: lock assign4 vacuum unlock
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
step lock:
SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
(1 row)
step assign4:
do $$
declare
r test2;
begin
select * into r from test1;
delete from test1;
commit;
perform pg_advisory_lock(1);
raise notice 'length(r) = %', length(r::text);
end;
$$;
<waiting ...>
step vacuum:
VACUUM test1;
step unlock:
SELECT pg_advisory_unlock(1);
pg_advisory_unlock
------------------
t
(1 row)
s1: NOTICE: length(r) = 6004
step assign4: <... completed>
starting permutation: lock assign5 vacuum unlock
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
step lock:
SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
(1 row)
step assign5:
do $$
declare
r record;
begin
for r in select test1.b from test1 loop
null;
end loop;
delete from test1;
commit;
perform pg_advisory_lock(1);
raise notice 'length(r) = %', length(r::text);
end;
$$;
<waiting ...>
step vacuum:
VACUUM test1;
step unlock:
SELECT pg_advisory_unlock(1);
pg_advisory_unlock
------------------
t
(1 row)
s1: NOTICE: length(r) = 6002
step assign5: <... completed>
starting permutation: lock assign6 vacuum unlock
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
step lock:
SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
(1 row)
step assign6:
do $$
declare
r record;
begin
insert into test1 values (2, repeat('bar', 3000));
insert into test1 values (3, repeat('baz', 4000));
for r in select test1.b from test1 loop
delete from test1;
commit;
perform pg_advisory_lock(1);
raise notice 'length(r) = %', length(r::text);
end loop;
end;
$$;
<waiting ...>
step vacuum:
VACUUM test1;
step unlock:
SELECT pg_advisory_unlock(1);
pg_advisory_unlock
------------------
t
(1 row)
s1: NOTICE: length(r) = 6002
s1: NOTICE: length(r) = 9002
s1: NOTICE: length(r) = 12002
step assign6: <... completed>
starting permutation: fetch-after-commit
pg_advisory_unlock_all
----------------------
(1 row)
pg_advisory_unlock_all
----------------------
(1 row)
s1: NOTICE: length(t) = 6000
s1: NOTICE: length(t) = 9000
s1: NOTICE: length(t) = 12000
step fetch-after-commit:
do $$
declare
r record;
t text;
begin
insert into test1 values (2, repeat('bar', 3000));
insert into test1 values (3, repeat('baz', 4000));
for r in select test1.a from test1 loop
commit;
select b into t from test1 where a = r.a;
raise notice 'length(t) = %', length(t);
end loop;
end;
$$;
|
