Import wiredtiger: cc2458c2c238b08db817161915d00d7e19c6ba29 from branch mongodb-4.4

ref: 943d9cdd2a..cc2458c2c2
for: 4.4.0-rc8

WT-6295       Aggregate time windows in salvage
WT-6297       Increase data size for test_checkpoint04.py
WT-6301       Add shorter running stress jobs
WT-6323       Increase cache size in prepare unit tests to avoid rollback errors
WT-6329       Add stats to track number of entries skipped by cursor next and prev
WT-6332       Don't configure HS cursor walk with test/format in-memory configuration
WT-6333       Fix memory leak in hs_cursor
WT-6334       Coverity: Use return value when closing incremental backup cursor
WT-6335       Formatting cleanups for history-store modify records
WT-6336       Minor cleanup in test/format buffer handling
WT-6337       Temporarily disable format's history store cursor scan
WT-6338       Retrieve at least one key to ensure it's valid for HS cursor scan
WT-6347       Don't reset transaction ids when evicting mixed mode tombstones and clear history store contents for mixed mode updates
WT-6350       Immediately evict the pages that are read by rollback to stable
WT-6352       Remove obsolete options from the wt verify API

14 files changed, 131 insertions, 221 deletions

diff --git a/src/third_party/wiredtiger/test/format/config.c b/src/third_party/wiredtiger/test/format/config.c
index b48bc0e18a2..dffde8eb25a 100644
--- a/src/third_party/wiredtiger/test/format/config.c
+++ b/src/third_party/wiredtiger/test/format/config.c
@@ -656,6 +656,8 @@ config_in_memory(void)
         return;
     if (config_is_perm("logging"))
         return;
+    if (config_is_perm("ops.hs_cursor"))
+        return;
     if (config_is_perm("ops.rebalance"))
         return;
     if (config_is_perm("ops.salvage"))
@@ -685,6 +687,8 @@ config_in_memory_reset(void)
         config_single("checkpoint=off", false);
     if (!config_is_perm("btree.compression"))
         config_single("btree.compression=none", false);
+    if (!config_is_perm("ops.hs_cursor"))
+        config_single("ops.hs_cursor=off", false);
     if (!config_is_perm("logging"))
         config_single("logging=off", false);
     if (!config_is_perm("ops.rebalance"))
diff --git a/src/third_party/wiredtiger/test/format/config.h b/src/third_party/wiredtiger/test/format/config.h
index 3ad4571d41f..80d2ab99cd4 100644
--- a/src/third_party/wiredtiger/test/format/config.h
+++ b/src/third_party/wiredtiger/test/format/config.h
@@ -228,8 +228,8 @@ static CONFIG c[] = {
   {"ops.compaction", "if compaction is running", C_BOOL, 10, 0, 0, &g.c_compact, NULL},
 
   /* 50% */
-  {"ops.history_store", "if history store cursor reads configured", C_BOOL, 50, 0, 0,
-    &g.c_hs_cursor, NULL},
+  {"ops.hs_cursor", "if history store cursor reads configured", C_BOOL, 50, 0, 0, &g.c_hs_cursor,
+    NULL},
 
   {"ops.pct.delete", "percent operations that are deletes", C_IGNORE, 0, 0, 100, &g.c_delete_pct,
     NULL},
diff --git a/src/third_party/wiredtiger/test/format/format.h b/src/third_party/wiredtiger/test/format/format.h
index 93e3ab54003..c8bafaaafd8 100644
--- a/src/third_party/wiredtiger/test/format/format.h
+++ b/src/third_party/wiredtiger/test/format/format.h
@@ -340,8 +340,6 @@ typedef struct {
     uint64_t insert_list[256]; /* column-store inserted records */
     u_int insert_list_cnt;
 
-    WT_ITEM *tbuf, _tbuf; /* temporary buffer */
-
 #define TINFO_RUNNING 1  /* Running */
 #define TINFO_COMPLETE 2 /* Finished */
 #define TINFO_JOINED 3   /* Resolved */
@@ -403,6 +401,6 @@ void wts_rebalance(void);
 void wts_reopen(void);
 void wts_salvage(void);
 void wts_stats(void);
-void wts_verify(const char *);
+void wts_verify(WT_CONNECTION *, const char *);
 
 #include "format.i"
diff --git a/src/third_party/wiredtiger/test/format/hs.c b/src/third_party/wiredtiger/test/format/hs.c
index e5d40e6256b..55b298f20e7 100644
--- a/src/third_party/wiredtiger/test/format/hs.c
+++ b/src/third_party/wiredtiger/test/format/hs.c
@@ -38,7 +38,7 @@ hs_cursor(void *arg)
     WT_CONNECTION *conn;
     WT_CURSOR *cursor;
     WT_DECL_RET;
-    WT_ITEM hs_key, hs_value;
+    WT_ITEM hs_key, hs_value, key;
     WT_SESSION *session;
     wt_timestamp_t hs_durable_timestamp, hs_start_ts, hs_stop_durable_ts;
     uint64_t hs_counter, hs_upd_type;
@@ -61,6 +61,7 @@ hs_cursor(void *arg)
 
     memset(&hs_key, 0, sizeof(hs_key));
     memset(&hs_value, 0, sizeof(hs_value));
+    memset(&key, 0, sizeof(key));
     hs_start_ts = 0; /* [-Wconditional-uninitialized] */
     hs_counter = 0;  /* [-Wconditional-uninitialized] */
     hs_btree_id = 0; /* [-Wconditional-uninitialized] */
@@ -81,13 +82,16 @@ hs_cursor(void *arg)
 
         /* Search to the last-known location. */
         if (!restart) {
-            cursor->set_key(cursor, hs_btree_id, &hs_key, hs_start_ts, hs_counter);
+            cursor->set_key(cursor, hs_btree_id, &key, hs_start_ts, hs_counter);
             ret = cursor->search_near(cursor, &exact);
             testutil_assert(ret == 0 || ret == WT_NOTFOUND);
         }
 
-        /* Get some more key/value pairs. */
-        for (i = mmrand(NULL, 0, 1000); i > 0; --i) {
+        /*
+         * Get some more key/value pairs. Always retrieve at least one key, that ensures we have a
+         * valid key when we copy it to start the next run.
+         */
+        for (i = mmrand(NULL, 1, 1000); i > 0; --i) {
             if ((ret = cursor->next(cursor)) == 0) {
                 testutil_check(
                   cursor->get_key(cursor, &hs_btree_id, &hs_key, &hs_start_ts, &hs_counter));
@@ -104,7 +108,7 @@ hs_cursor(void *arg)
          * Otherwise, reset so we'll start over.
          */
         if (ret == 0) {
-            testutil_check(__wt_buf_grow(CUR2S(cursor), &hs_key, hs_key.size));
+            testutil_check(__wt_buf_set(CUR2S(cursor), &key, hs_key.data, hs_key.size));
             restart = false;
         } else
             restart = true;
@@ -118,6 +122,7 @@ hs_cursor(void *arg)
             break;
     }
 
+    __wt_buf_free(CUR2S(cursor), &key);
     testutil_check(session->close(session, NULL));
 
     return (WT_THREAD_RET_VALUE);
diff --git a/src/third_party/wiredtiger/test/format/ops.c b/src/third_party/wiredtiger/test/format/ops.c
index ac77565170e..82aa22d5f40 100644
--- a/src/third_party/wiredtiger/test/format/ops.c
+++ b/src/third_party/wiredtiger/test/format/ops.c
@@ -628,7 +628,6 @@ ops(void *arg)
     val_gen_init(tinfo->value);
     tinfo->lastkey = &tinfo->_lastkey;
     key_gen_init(tinfo->lastkey);
-    tinfo->tbuf = &tinfo->_tbuf;
 
     /* Set the first operation where we'll create sessions and cursors. */
     cursor = NULL;
@@ -1008,7 +1007,6 @@ rollback:
     key_gen_teardown(tinfo->key);
     val_gen_teardown(tinfo->value);
     key_gen_teardown(tinfo->lastkey);
-    free(tinfo->tbuf->mem);
 
     tinfo->state = TINFO_COMPLETE;
     return (WT_THREAD_RET_VALUE);
@@ -1249,16 +1247,13 @@ order_error_col:
                 goto order_error_row;
             if (!record_gaps) {
                 /*
-                 * Convert the keys to record numbers and then compare less-than-or-equal. (Not
+                 * Convert the keys to record numbers and then compare less-than-or-equal. (It's not
                  * less-than, row-store inserts new rows in-between rows by appending a new suffix
-                 * to the row's key.)
+                 * to the row's key.) Keys are strings with terminating '/' values, so absent key
+                 * corruption, we can simply do the underlying string conversion on the key string.
                  */
-                testutil_check(__wt_buf_fmt(CUR2S(cursor), tinfo->tbuf, "%.*s",
-                  (int)tinfo->key->size, (char *)tinfo->key->data));
-                keyno_prev = strtoul(tinfo->tbuf->data, NULL, 10);
-                testutil_check(__wt_buf_fmt(
-                  CUR2S(cursor), tinfo->tbuf, "%.*s", (int)key.size, (char *)key.data));
-                keyno = strtoul(tinfo->tbuf->data, NULL, 10);
+                keyno_prev = strtoul(tinfo->key->data, NULL, 10);
+                keyno = strtoul(key.data, NULL, 10);
                 if (incrementing) {
                     if (keyno_prev != keyno && keyno_prev + 1 != keyno)
                         goto order_error_row;
diff --git a/src/third_party/wiredtiger/test/format/salvage.c b/src/third_party/wiredtiger/test/format/salvage.c
index 8f8d3c12786..0e922a71627 100644
--- a/src/third_party/wiredtiger/test/format/salvage.c
+++ b/src/third_party/wiredtiger/test/format/salvage.c
@@ -139,16 +139,14 @@ wts_salvage(void)
     /* Salvage, then verify. */
     wts_open(g.home, &conn, &session, true);
     testutil_check(session->salvage(session, g.uri, "force=true"));
-
-#if 0
-    wts_verify("post-salvage verify");
-#endif
+    wts_verify(conn, "post-salvage verify");
     wts_close(&conn, &session);
 
     /* Corrupt the file randomly, salvage, then verify. */
     if (corrupt()) {
         wts_open(g.home, &conn, &session, false);
         testutil_check(session->salvage(session, g.uri, "force=true"));
+        wts_verify(conn, "post-corrupt-salvage verify");
         wts_close(&conn, &session);
     }
 }
diff --git a/src/third_party/wiredtiger/test/format/smoke.sh b/src/third_party/wiredtiger/test/format/smoke.sh
index 067ef8e2589..de46580c078 100755
--- a/src/third_party/wiredtiger/test/format/smoke.sh
+++ b/src/third_party/wiredtiger/test/format/smoke.sh
@@ -3,7 +3,6 @@
 set -e
 
 # Smoke-test format as part of running "make check".
-args="-1 -c . "
 args="$args btree.compression=none "
 args="$args logging_compression=none"
 args="$args runs.ops=50000 "
@@ -11,11 +10,18 @@ args="$args runs.rows=10000 "
 args="$args runs.source=table "
 args="$args runs.threads=4 "
 
+# Locate format.sh from home directory.
+FORMAT_SCRIPT=$(git rev-parse --show-toplevel)/test/format/format.sh
+
 # Temporarily disabled
-# $TEST_WRAPPER ./t $args runs.type=fix
-# $TEST_WRAPPER ./t $args runs.type=row runs.source=lsm
-# $TEST_WRAPPER ./t $args runs.type=var
+# $FORMAT_SCRIPT -t 2 $args runs.type=fix
+# $FORMAT_SCRIPT -t 2 $args runs.type=row runs.source=lsm
+# $FORMAT_SCRIPT -t 2 $args runs.type=var
+
+# Run the format script for 10 minutues, distribute it across the number
+# of different test arguments.
+
+# This will run the test/format binary for 5 minutes each.
+$FORMAT_SCRIPT -t 5 $args runs.type=row
 
-$TEST_WRAPPER ./t $args runs.type=row
-# Force a rebalance to occur with statistics logging to test the utility
-$TEST_WRAPPER ./t $args runs.type=row statistics.server=1 ops.rebalance=1
+$FORMAT_SCRIPT -t 5 $args runs.type=row statistics.server=1 ops.rebalance=1
diff --git a/src/third_party/wiredtiger/test/format/t.c b/src/third_party/wiredtiger/test/format/t.c
index d363c037ae7..de329749335 100644
--- a/src/third_party/wiredtiger/test/format/t.c
+++ b/src/third_party/wiredtiger/test/format/t.c
@@ -274,7 +274,7 @@ main(int argc, char *argv[])
             trace_init();
 
             TIMED_MAJOR_OP(wts_load()); /* Load and verify initial records */
-            TIMED_MAJOR_OP(wts_verify("post-bulk verify"));
+            TIMED_MAJOR_OP(wts_verify(g.wts_conn, "post-bulk verify"));
         }
 
         TIMED_MAJOR_OP(wts_read_scan());
@@ -292,7 +292,7 @@ main(int argc, char *argv[])
          * Verify the objects. Verify closes the underlying handle and discards the statistics, read
          * them first.
          */
-        TIMED_MAJOR_OP(wts_verify("post-ops verify"));
+        TIMED_MAJOR_OP(wts_verify(g.wts_conn, "post-ops verify"));
 
         track("shutting down", 0ULL, NULL);
         wts_close(&g.wts_conn, NULL);
diff --git a/src/third_party/wiredtiger/test/format/wts.c b/src/third_party/wiredtiger/test/format/wts.c
index 91b8c5051aa..f822a6e8bea 100644
--- a/src/third_party/wiredtiger/test/format/wts.c
+++ b/src/third_party/wiredtiger/test/format/wts.c
@@ -487,16 +487,14 @@ wts_close(WT_CONNECTION **connp, WT_SESSION **sessionp)
 }
 
 void
-wts_verify(const char *tag)
+wts_verify(WT_CONNECTION *conn, const char *tag)
 {
-    WT_CONNECTION *conn;
     WT_DECL_RET;
     WT_SESSION *session;
 
     if (g.c_verify == 0)
         return;
 
-    conn = g.wts_conn;
     track("verify", 0ULL, NULL);
 
     testutil_check(conn->open_session(conn, NULL, NULL, &session));
diff --git a/src/third_party/wiredtiger/test/suite/test_checkpoint04.py b/src/third_party/wiredtiger/test/suite/test_checkpoint04.py
index b2af62ce4a1..710025067f7 100755
--- a/src/third_party/wiredtiger/test/suite/test_checkpoint04.py
+++ b/src/third_party/wiredtiger/test/suite/test_checkpoint04.py
@@ -68,63 +68,72 @@ class test_checkpoint04(wttest.WiredTigerTestCase):
 
     def test_checkpoint_stats(self):
         nrows = 100
-        ntables = 5
-
-        # Create many tables and perform many updates so our checkpoint stats are populated.
-        value = "wired" * 100
-        tables = self.create_tables(ntables)
-        for uri, ds in tables.items():
-            self.add_updates(uri, ds, value, nrows)
-
-        # Perform a checkpoint.
-        self.session.checkpoint()
-
-        # Update the tables.
-        value = "tiger" * 100
-        tables = self.create_tables(ntables)
-        for uri, ds in tables.items():
-            self.add_updates(uri, ds, value, nrows)
-
-        # Perform a checkpoint.
-        self.session.checkpoint()
-
-        # Check the statistics.
-        # Set them into a variable so that we can print them all out. We've had a failure
-        # on Windows that is very difficult to reproduce so collect what info we can.
-        num_ckpt = self.get_stat(stat.conn.txn_checkpoint)
-        self.pr('txn_checkpoint, number of checkpoints ' + str(num_ckpt))
-        running = self.get_stat(stat.conn.txn_checkpoint_running)
-        self.pr('txn_checkpoint_running ' + str(running))
-        prep_running = self.get_stat(stat.conn.txn_checkpoint_prep_running)
-        self.pr('txn_checkpoint_prep_running ' + str(prep_running))
-
-        prep_min = self.get_stat(stat.conn.txn_checkpoint_prep_min)
-        self.pr('txn_checkpoint_prep_min ' + str(prep_min))
-        time_min = self.get_stat(stat.conn.txn_checkpoint_time_min)
-        self.pr('txn_checkpoint_time_min ' + str(time_min))
-
-        prep_max = self.get_stat(stat.conn.txn_checkpoint_prep_max)
-        self.pr('txn_checkpoint_prep_max ' + str(prep_max))
-        time_max = self.get_stat(stat.conn.txn_checkpoint_time_max)
-        self.pr('txn_checkpoint_time_max ' + str(time_max))
-
-        prep_recent = self.get_stat(stat.conn.txn_checkpoint_prep_recent)
-        self.pr('txn_checkpoint_prep_recent ' + str(prep_recent))
-        time_recent = self.get_stat(stat.conn.txn_checkpoint_time_recent)
-        self.pr('txn_checkpoint_time_recent ' + str(time_recent))
-
-        prep_total = self.get_stat(stat.conn.txn_checkpoint_prep_total)
-        self.pr('txn_checkpoint_prep_total ' + str(prep_total))
-        time_total = self.get_stat(stat.conn.txn_checkpoint_time_total)
-        self.pr('txn_checkpoint_time_total ' + str(time_total))
-
-        self.assertEqual(num_ckpt, 2)
-        self.assertEqual(running, 0)
-        self.assertEqual(prep_running, 0)
-        self.assertLess(prep_min, time_min)
-        self.assertLess(prep_max, time_max)
-        self.assertLess(prep_recent, time_recent)
-        self.assertLess(prep_total, time_total)
+        ntables = 10
+        multiplier = 1
+
+        # Run the loop and increase the value size with each iteration until
+        # the test passes.
+        while True:
+            # Create many tables and perform many updates so our checkpoint stats are populated.
+            value = "wired" * 100 * multiplier
+            tables = self.create_tables(ntables)
+            for uri, ds in tables.items():
+                self.add_updates(uri, ds, value, nrows)
+
+            # Perform a checkpoint.
+            self.session.checkpoint()
+
+            # Update the tables.
+            value = "tiger" * 100 * multiplier
+            tables = self.create_tables(ntables)
+            for uri, ds in tables.items():
+                self.add_updates(uri, ds, value, nrows)
+
+            # Perform a checkpoint.
+            self.session.checkpoint()
+
+            # Check the statistics.
+            # Set them into a variable so that we can print them all out. We've had a failure
+            # on Windows that is very difficult to reproduce so collect what info we can.
+            num_ckpt = self.get_stat(stat.conn.txn_checkpoint)
+            self.pr('txn_checkpoint, number of checkpoints ' + str(num_ckpt))
+            running = self.get_stat(stat.conn.txn_checkpoint_running)
+            self.pr('txn_checkpoint_running ' + str(running))
+            prep_running = self.get_stat(stat.conn.txn_checkpoint_prep_running)
+            self.pr('txn_checkpoint_prep_running ' + str(prep_running))
+
+            prep_min = self.get_stat(stat.conn.txn_checkpoint_prep_min)
+            self.pr('txn_checkpoint_prep_min ' + str(prep_min))
+            time_min = self.get_stat(stat.conn.txn_checkpoint_time_min)
+            self.pr('txn_checkpoint_time_min ' + str(time_min))
+
+            prep_max = self.get_stat(stat.conn.txn_checkpoint_prep_max)
+            self.pr('txn_checkpoint_prep_max ' + str(prep_max))
+            time_max = self.get_stat(stat.conn.txn_checkpoint_time_max)
+            self.pr('txn_checkpoint_time_max ' + str(time_max))
+
+            prep_recent = self.get_stat(stat.conn.txn_checkpoint_prep_recent)
+            self.pr('txn_checkpoint_prep_recent ' + str(prep_recent))
+            time_recent = self.get_stat(stat.conn.txn_checkpoint_time_recent)
+            self.pr('txn_checkpoint_time_recent ' + str(time_recent))
+
+            prep_total = self.get_stat(stat.conn.txn_checkpoint_prep_total)
+            self.pr('txn_checkpoint_prep_total ' + str(prep_total))
+            time_total = self.get_stat(stat.conn.txn_checkpoint_time_total)
+            self.pr('txn_checkpoint_time_total ' + str(time_total))
+
+            self.assertEqual(num_ckpt, 2 * multiplier)
+            self.assertEqual(running, 0)
+            self.assertEqual(prep_running, 0)
+            # Assert if this loop continues for more than 100 iterations.
+            self.assertLess(multiplier, 100)
+
+            # This condition is mainly to confirm that prep's stats time are always less than time's stats time.
+            # Run the loop again if any of the below condition fails and exit if the test passes.
+            if prep_min < time_min and prep_max < time_max and prep_recent < time_recent and prep_total < time_total:
+                break
+            else:
+                multiplier += 1
 
 if __name__ == '__main__':
     wttest.run()
diff --git a/src/third_party/wiredtiger/test/suite/test_hs11.py b/src/third_party/wiredtiger/test/suite/test_hs11.py
index efc9d02401c..f7d31c6796f 100644
--- a/src/third_party/wiredtiger/test/suite/test_hs11.py
+++ b/src/third_party/wiredtiger/test/suite/test_hs11.py
@@ -32,13 +32,12 @@ def timestamp_str(t):
     return '%x' % t
 
 # test_hs11.py
-# Ensure that when we delete a key due to a tombstone being globally visible, we delete its
-# associated history store content.
+# Ensure that mixed mode updates clear the history store records.
 class test_hs11(wttest.WiredTigerTestCase):
     conn_config = 'cache_size=50MB'
     session_config = 'isolation=snapshot'
 
-    def test_key_deletion_clears_hs(self):
+    def run_test(self, update_type):
         uri = 'table:test_hs11'
         create_params = 'key_format=S,value_format=S'
         self.session.create(uri, create_params)
@@ -58,14 +57,16 @@ class test_hs11(wttest.WiredTigerTestCase):
         # Reconcile and flush versions 1-3 to the history store.
         self.session.checkpoint()
 
-        # Apply a non-timestamped tombstone. When the pages get evicted, the keys will get deleted
-        # since the tombstone is globally visible.
+        # Apply a mixed mode update.
         for i in range(1, 10000):
             if i % 2 == 0:
-                cursor.set_key(str(i))
-                cursor.remove()
+                if update_type == 'deletion':
+                    cursor.set_key(str(i))
+                    cursor.remove()
+                else:
+                    cursor[str(i)] = value2
 
-        # Now apply an update at timestamp 10 to recreate each key.
+        # Now apply an update at timestamp 10.
         for i in range(1, 10000):
             self.session.begin_transaction()
             cursor[str(i)] = value2
@@ -76,8 +77,17 @@ class test_hs11(wttest.WiredTigerTestCase):
             self.session.begin_transaction('read_timestamp=' + timestamp_str(ts))
             for i in range(1, 10000):
                 if i % 2 == 0:
-                    cursor.set_key(str(i))
-                    self.assertEqual(cursor.search(), wiredtiger.WT_NOTFOUND)
+                    if update_type == 'deletion':
+                        cursor.set_key(str(i))
+                        self.assertEqual(cursor.search(), wiredtiger.WT_NOTFOUND)
+                    else:
+                        self.assertEqual(cursor[str(i)], value2)
                 else:
                     self.assertEqual(cursor[str(i)], value1)
             self.session.rollback_transaction()
+
+    def test_key_deletion_clears_hs(self):
+        self.run_test('deletion')
+
+    def test_key_update_clears_hs(self):
+        self.run_test('update')
diff --git a/src/third_party/wiredtiger/test/suite/test_prepare08.py b/src/third_party/wiredtiger/test/suite/test_prepare08.py
index 0ebcec952ce..f3eb9d12881 100644
--- a/src/third_party/wiredtiger/test/suite/test_prepare08.py
+++ b/src/third_party/wiredtiger/test/suite/test_prepare08.py
@@ -37,9 +37,9 @@ def timestamp_str(t):
 # test_prepare07.py
 # Test to ensure prepared tombstones are properly aborted even when they are written
 # to the data store.
-class test_prepare07(wttest.WiredTigerTestCase):
+class test_prepare08(wttest.WiredTigerTestCase):
     # Force a small cache.
-    conn_config = 'cache_size=1MB'
+    conn_config = 'cache_size=2MB'
 
     def updates(self, ds, uri, nrows, value, ts):
         cursor = self.session.open_cursor(uri)
diff --git a/src/third_party/wiredtiger/test/suite/test_prepare10.py b/src/third_party/wiredtiger/test/suite/test_prepare10.py
index 7df96ffd2c0..ba1a29718ed 100644
--- a/src/third_party/wiredtiger/test/suite/test_prepare10.py
+++ b/src/third_party/wiredtiger/test/suite/test_prepare10.py
@@ -34,12 +34,12 @@ from wtdataset import SimpleDataSet
 def timestamp_str(t):
     return '%x' % t
 
-# test_prepare07.py
+# test_prepare10.py
 # Test to ensure prepared tombstones are properly aborted even when they are written
 # to the data store.
-class test_prepare07(wttest.WiredTigerTestCase):
+class test_prepare10(wttest.WiredTigerTestCase):
     # Force a small cache.
-    conn_config = 'cache_size=1MB'
+    conn_config = 'cache_size=2MB'
     session_config = 'isolation=snapshot'
 
     def updates(self, ds, uri, nrows, value, ts):
diff --git a/src/third_party/wiredtiger/test/suite/test_timestamp19.py b/src/third_party/wiredtiger/test/suite/test_timestamp19.py
deleted file mode 100755
index bb28dce6703..00000000000
--- a/src/third_party/wiredtiger/test/suite/test_timestamp19.py
+++ /dev/null
@@ -1,113 +0,0 @@
-#!/usr/bin/env python
-#
-# Public Domain 2014-2020 MongoDB, Inc.
-# Public Domain 2008-2014 WiredTiger, Inc.
-#
-# This is free and unencumbered software released into the public domain.
-#
-# Anyone is free to copy, modify, publish, use, compile, sell, or
-# distribute this software, either in source code form or as a compiled
-# binary, for any purpose, commercial or non-commercial, and by any
-# means.
-#
-# In jurisdictions that recognize copyright laws, the author or authors
-# of this software dedicate any and all copyright interest in the
-# software to the public domain. We make this dedication for the benefit
-# of the public at large and to the detriment of our heirs and
-# successors. We intend this dedication to be an overt act of
-# relinquishment in perpetuity of all present and future rights to this
-# software under copyright law.
-#
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
-# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
-# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
-# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
-# OTHER DEALINGS IN THE SOFTWARE.
-#
-# test_timestamp19.py
-# Use the oldest checkpoint timestamp in the history store as the minimum valid oldest
-# timestamp on restart.
-#
-
-import wiredtiger, wttest
-from wtdataset import SimpleDataSet
-
-def timestamp_str(t):
-    return '%x' % t
-
-class test_timestamp19(wttest.WiredTigerTestCase):
-    conn_config = 'cache_size=50MB,log=(enabled),statistics=(all)'
-    session_config = 'isolation=snapshot'
-
-    def updates(self, uri, value, ds, nrows, commit_ts):
-        session = self.session
-        cursor = session.open_cursor(uri)
-        for i in range(0, nrows):
-            session.begin_transaction()
-            cursor[ds.key(i)] = value
-            session.commit_transaction('commit_timestamp=' + timestamp_str(commit_ts))
-        cursor.close()
-
-    def test_timestamp(self):
-        uri = "table:test_timestamp19"
-        create_params = 'value_format=S,key_format=i'
-        self.session.create(uri, create_params)
-
-        ds = SimpleDataSet(
-            self, uri, 0, key_format="i", value_format="S", config='log=(enabled=false)')
-        ds.populate()
-
-        nrows = 1000
-        value_x = 'x' * 1000
-        value_y = 'y' * 1000
-        value_z = 'z' * 1000
-
-        # Set the oldest and stable timestamps to 10.
-        self.conn.set_timestamp('oldest_timestamp=' + timestamp_str(10) +
-          ', stable_timestamp=' + timestamp_str(10))
-
-        # Insert values with varying timestamps.
-        self.updates(uri, value_x, ds, nrows, 20)
-        self.updates(uri, value_y, ds, nrows, 30)
-        self.updates(uri, value_z, ds, nrows, 40)
-
-        # Perform a checkpoint.
-        self.session.checkpoint('use_timestamp=true')
-
-        # Move the oldest and stable timestamps to 40.
-        self.conn.set_timestamp('oldest_timestamp=' + timestamp_str(40) +
-          ', stable_timestamp=' + timestamp_str(40))
-
-        # Update values.
-        self.updates(uri, value_z, ds, nrows, 50)
-        self.updates(uri, value_x, ds, nrows, 60)
-        self.updates(uri, value_y, ds, nrows, 70)
-
-        # Perform a checkpoint.
-        self.session.checkpoint('use_timestamp=true')
-
-        # Close and reopen the connection.
-        self.close_conn()
-        self.conn = self.setUpConnectionOpen('.')
-        self.session = self.setUpSessionOpen(self.conn)
-
-        # The oldest timestamp on recovery is 40. Trying to set it earlier is a no-op.
-        self.conn.set_timestamp('oldest_timestamp=' + timestamp_str(10))
-        self.assertTimestampsEqual(self.conn.query_timestamp('get=oldest'), timestamp_str(40))
-
-        # Trying to set an earlier stable timestamp is an error.
-        self.assertRaisesWithMessage(wiredtiger.WiredTigerError,
-            lambda: self.conn.set_timestamp('stable_timestamp=' + timestamp_str(10)),
-            '/oldest timestamp \(0, 40\) must not be later than stable timestamp \(0, 10\)/')
-        self.assertTimestampsEqual(self.conn.query_timestamp('get=stable'), timestamp_str(40))
-
-        # Move the oldest and stable timestamps to 70.
-        self.conn.set_timestamp('oldest_timestamp=' + timestamp_str(70) +
-          ', stable_timestamp=' + timestamp_str(70))
-        self.assertTimestampsEqual(self.conn.query_timestamp('get=oldest'), timestamp_str(70))
-        self.assertTimestampsEqual(self.conn.query_timestamp('get=stable'), timestamp_str(70))
-
-if __name__ == '__main__':
-    wttest.run()