Parsed test spec with 3 sessions

starting permutation: s0_vacuum s1_plan s1_fetches s1_begin s2_begin s1_read s2_read s1_update s2_update s1_commit s2_commit
step s0_vacuum: VACUUM bss;
step s1_plan: EXPLAIN (COSTS OFF) SELECT id, k FROM bss WHERE c = 1 ORDER BY k, id LIMIT 3;
QUERY PLAN                            
--------------------------------------
Limit                                 
  ->  Custom Scan (LionOrdered) on bss
        Ordered By: bss_k (index only)
        Lion Cond: (c = 1)            
        Lion Indexes: bss_c           
(5 rows)

step s1_fetches: SELECT bss_fetches('SELECT id, k FROM bss WHERE c = 1 ORDER BY k, id LIMIT 3');
bss_fetches                                    
-----------------------------------------------
Ordered By: bss_k (index only); Heap Fetches: 0
(1 row)

step s1_begin: BEGIN ISOLATION LEVEL SERIALIZABLE;
step s2_begin: BEGIN ISOLATION LEVEL SERIALIZABLE;
step s1_read: SELECT id, k FROM bss WHERE c = 1 ORDER BY k, id LIMIT 3;
 id|k
---+-
191|4
491|5
791|6
(3 rows)

step s2_read: SELECT id, k FROM bss WHERE c = 2 ORDER BY k, id LIMIT 3;
 id|k
---+-
 82|7
382|8
682|9
(3 rows)

step s1_update: UPDATE bss SET note = 's1' WHERE id = 82;
step s2_update: UPDATE bss SET note = 's2' WHERE id = 191;
step s1_commit: COMMIT;
step s2_commit: COMMIT;
ERROR:  could not serialize access due to read/write dependencies among transactions

starting permutation: s0_vacuum s1_fetches s1_begin s2_begin s1_read s2_read s1_update s1_commit s2_update s2_commit
step s0_vacuum: VACUUM bss;
step s1_fetches: SELECT bss_fetches('SELECT id, k FROM bss WHERE c = 1 ORDER BY k, id LIMIT 3');
bss_fetches                                    
-----------------------------------------------
Ordered By: bss_k (index only); Heap Fetches: 0
(1 row)

step s1_begin: BEGIN ISOLATION LEVEL SERIALIZABLE;
step s2_begin: BEGIN ISOLATION LEVEL SERIALIZABLE;
step s1_read: SELECT id, k FROM bss WHERE c = 1 ORDER BY k, id LIMIT 3;
 id|k
---+-
191|4
491|5
791|6
(3 rows)

step s2_read: SELECT id, k FROM bss WHERE c = 2 ORDER BY k, id LIMIT 3;
 id|k
---+-
 82|7
382|8
682|9
(3 rows)

step s1_update: UPDATE bss SET note = 's1' WHERE id = 82;
step s1_commit: COMMIT;
step s2_update: UPDATE bss SET note = 's2' WHERE id = 191;
ERROR:  could not serialize access due to read/write dependencies among transactions
step s2_commit: COMMIT;