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);
step s1c: COMMIT;
step s2u: UPDATE parent SET aux = 'baz';
ERROR:  could not serialize access due to concurrent update
step s2c: COMMIT;

starting permutation: s1i s1u s2i s2u s1c s2c
step s1i: INSERT INTO child VALUES (1, 1);
step s1u: UPDATE parent SET aux = 'bar';
step s2i: INSERT INTO child VALUES (2, 1);
step s2u: UPDATE parent SET aux = 'baz'; <waiting ...>
step s1c: COMMIT;
step s2u: <... completed>
ERROR:  could not serialize access due to concurrent update
step s2c: COMMIT;

starting permutation: s1i s2i s1u s1c s2u s2c
step s1i: INSERT INTO child VALUES (1, 1);
step s2i: INSERT INTO child VALUES (2, 1);
step s1u: UPDATE parent SET aux = 'bar';
step s1c: COMMIT;
step s2u: UPDATE parent SET aux = 'baz';
ERROR:  could not serialize access due to concurrent update
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';
step s2u: UPDATE parent SET aux = 'baz'; <waiting ...>
step s1c: COMMIT;
step s2u: <... completed>
ERROR:  could not serialize access due to concurrent update
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';
step s1u: UPDATE parent SET aux = 'bar'; <waiting ...>
step s2c: COMMIT;
step s1u: <... completed>
ERROR:  could not serialize access due to concurrent update
step s1c: COMMIT;

starting permutation: s1i s2i s2u s2c s1u s1c
step s1i: INSERT INTO child VALUES (1, 1);
step s2i: INSERT INTO child VALUES (2, 1);
step s2u: UPDATE parent SET aux = 'baz';
step s2c: COMMIT;
step s1u: UPDATE parent SET aux = 'bar';
ERROR:  could not serialize access due to concurrent update
step s1c: COMMIT;

starting permutation: s2i s1i s1u s1c s2u s2c
step s2i: INSERT INTO child VALUES (2, 1);
step s1i: INSERT INTO child VALUES (1, 1);
step s1u: UPDATE parent SET aux = 'bar';
step s1c: COMMIT;
step s2u: UPDATE parent SET aux = 'baz';
ERROR:  could not serialize access due to concurrent update
step s2c: 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';
step s2u: UPDATE parent SET aux = 'baz'; <waiting ...>
step s1c: COMMIT;
step s2u: <... completed>
ERROR:  could not serialize access due to concurrent update
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';
step s1u: UPDATE parent SET aux = 'bar'; <waiting ...>
step s2c: COMMIT;
step s1u: <... completed>
ERROR:  could not serialize access due to concurrent update
step s1c: COMMIT;

starting permutation: s2i s1i s2u s2c s1u s1c
step s2i: INSERT INTO child VALUES (2, 1);
step s1i: INSERT INTO child VALUES (1, 1);
step s2u: UPDATE parent SET aux = 'baz';
step s2c: COMMIT;
step s1u: UPDATE parent SET aux = 'bar';
ERROR:  could not serialize access due to concurrent update
step s1c: COMMIT;

starting permutation: s2i s2u s1i s1u s2c s1c
step s2i: INSERT INTO child VALUES (2, 1);
step s2u: UPDATE parent SET aux = 'baz';
step s1i: INSERT INTO child VALUES (1, 1);
step s1u: UPDATE parent SET aux = 'bar'; <waiting ...>
step s2c: COMMIT;
step s1u: <... completed>
ERROR:  could not serialize access due to concurrent update
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);
step s2c: COMMIT;
step s1u: UPDATE parent SET aux = 'bar';
ERROR:  could not serialize access due to concurrent update
step s1c: COMMIT;

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