Parsed test spec with 2 sessions

starting permutation: s1i s1u s1c s2i s2u s2c
step s1i:  INSERT INTO child VALUES (1, 1); 
step s1u:  UPDATE parent SET aux = 'bar'; 
step s1c:  COMMIT; 
step s2i:  INSERT INTO child VALUES (2, 1); 
step s2u:  UPDATE parent SET aux = 'baz'; 
step s2c:  COMMIT; 

starting permutation: s1i s1u s2i s1c s2u s2c
step s1i:  INSERT INTO child VALUES (1, 1); 
step s1u:  UPDATE parent SET aux = 'bar'; 
step s2i:  INSERT INTO child VALUES (2, 1);  <waiting ...>
step s1c:  COMMIT; 
step s2i: <... completed>
step s2u:  UPDATE parent SET aux = 'baz'; 
step s2c:  COMMIT; 

starting permutation: s1i s2i s1u s2u s1c s2c
step s1i:  INSERT INTO child VALUES (1, 1); 
step s2i:  INSERT INTO child VALUES (2, 1); 
step s1u:  UPDATE parent SET aux = 'bar';  <waiting ...>
step s2u:  UPDATE parent SET aux = 'baz'; 
step s1u: <... completed>
ERROR:  deadlock detected
step s1c:  COMMIT; 
step s2c:  COMMIT; 

starting permutation: s1i s2i s2u s1u s2c s1c
step s1i:  INSERT INTO child VALUES (1, 1); 
step s2i:  INSERT INTO child VALUES (2, 1); 
step s2u:  UPDATE parent SET aux = 'baz';  <waiting ...>
step s1u:  UPDATE parent SET aux = 'bar'; 
ERROR:  deadlock detected
step s2u: <... completed>
step s2c:  COMMIT; 
step s1c:  COMMIT; 

starting permutation: s2i s1i s1u s2u s1c s2c
step s2i:  INSERT INTO child VALUES (2, 1); 
step s1i:  INSERT INTO child VALUES (1, 1); 
step s1u:  UPDATE parent SET aux = 'bar';  <waiting ...>
step s2u:  UPDATE parent SET aux = 'baz'; 
step s1u: <... completed>
ERROR:  deadlock detected
step s1c:  COMMIT; 
step s2c:  COMMIT; 

starting permutation: s2i s1i s2u s1u s2c s1c
step s2i:  INSERT INTO child VALUES (2, 1); 
step s1i:  INSERT INTO child VALUES (1, 1); 
step s2u:  UPDATE parent SET aux = 'baz';  <waiting ...>
step s1u:  UPDATE parent SET aux = 'bar'; 
ERROR:  deadlock detected
step s2u: <... completed>
step s2c:  COMMIT; 
step s1c:  COMMIT; 

starting permutation: s2i s2u s1i s2c s1u s1c
step s2i:  INSERT INTO child VALUES (2, 1); 
step s2u:  UPDATE parent SET aux = 'baz'; 
step s1i:  INSERT INTO child VALUES (1, 1);  <waiting ...>
step s2c:  COMMIT; 
step s1i: <... completed>
step s1u:  UPDATE parent SET aux = 'bar'; 
step s1c:  COMMIT; 
