SERVER-66770 Add more WiredTiger configurations to config fuzz

1 files changed, 37 insertions, 3 deletions

diff --git a/buildscripts/resmokelib/mongod_fuzzer_configs.py b/buildscripts/resmokelib/mongod_fuzzer_configs.py
index a9750997fef..7fa8143ba72 100644
--- a/buildscripts/resmokelib/mongod_fuzzer_configs.py
+++ b/buildscripts/resmokelib/mongod_fuzzer_configs.py
@@ -21,17 +21,49 @@ def generate_eviction_configs(rng):
     assert eviction_dirty_trigger > eviction_dirty_target
     assert eviction_dirty_trigger <= trigger_max
 
+    # Fuzz eviction_updates_target and eviction_updates_trigger. These are by default half the
+    # values of the corresponding eviction dirty target and trigger. They need to stay less than the
+    # dirty equivalents. The default updates target is 2.5% of the cache, so let's start fuzzing
+    # from 2%.
+    updates_target_min = 2 if eviction_dirty_target <= 100 else 20 * 1024 * 1024  # 2% of 1GB cache
+    eviction_updates_target = rng.randint(updates_target_min, eviction_dirty_target - 1)
+    eviction_updates_trigger = rng.randint(eviction_updates_target + 1, eviction_dirty_trigger - 1)
+
+    # Fuzz File manager settings
     close_idle_time_secs = rng.randint(1, 100)
     close_handle_minimum = rng.randint(0, 1000)
     close_scan_interval = rng.randint(1, 100)
 
-    return "eviction_checkpoint_target={0},eviction_dirty_target={1},eviction_dirty_trigger={2},"\
-           "eviction_target={3},eviction_trigger={4},file_manager=(close_handle_minimum={5},"\
-           "close_idle_time={6},close_scan_interval={7})".format(eviction_checkpoint_target,
+    # The debug_mode for WiredTiger offers some settings to change internal behavior that could help
+    # find bugs. Settings to fuzz:
+    # eviction - Turns aggressive eviction on/off
+    # realloc_exact - Finds more memory bugs by allocating the memory for the exact size asked
+    # rollback_error - Forces WiredTiger to return a rollback error every Nth call
+    # slow_checkpoint - Adds internal delays in processing internal leaf pages during a checkpoint
+    dbg_eviction = rng.choice(['true', 'false'])
+    dbg_realloc_exact = rng.choice(['true', 'false'])
+    # Rollback every Nth transaction. The values have been tuned after looking at how many
+    # WiredTiger transactions happen per second for the config-fuzzed jstests.
+    # The setting is trigerring bugs, disabled until they get resolved.
+    # dbg_rollback_error = rng.choice([0, rng.randint(250, 1500)])
+    dbg_rollback_error = 0
+    dbg_slow_checkpoint = rng.choice(['true', 'false'])
+
+    return "debug_mode=(eviction={0},realloc_exact={1},rollback_error={2}, slow_checkpoint={3}),"\
+           "eviction_checkpoint_target={4},eviction_dirty_target={5},eviction_dirty_trigger={6},"\
+           "eviction_target={7},eviction_trigger={8},eviction_updates_target={9},"\
+           "eviction_updates_trigger={10},file_manager=(close_handle_minimum={11},"\
+           "close_idle_time={12},close_scan_interval={13})".format(dbg_eviction,
+                                                                 dbg_realloc_exact,
+                                                                 dbg_rollback_error,
+                                                                 dbg_slow_checkpoint,
+                                                                 eviction_checkpoint_target,
                                                                  eviction_dirty_target,
                                                                  eviction_dirty_trigger,
                                                                  eviction_target,
                                                                  eviction_trigger,
+                                                                 eviction_updates_target,
+                                                                 eviction_updates_trigger,
                                                                  close_handle_minimum,
                                                                  close_idle_time_secs,
                                                                  close_scan_interval)
@@ -92,6 +124,8 @@ def generate_independent_parameters(rng):
         # The old retryable writes format is used by other variants. Weight towards turning on the
         # new retryable writes format on in this one.
         ret["storeFindAndModifyImagesInSideCollection"] = True
+    ret["syncdelay"] = rng.choice([60, rng.randint(15, 180)])
+    ret["minSnapshotHistoryWindowInSeconds"] = rng.choice([300, rng.randint(5, 600)])
 
     return ret