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diff --git a/src/third_party/wiredtiger/test/suite/test_prepare_hs04.py b/src/third_party/wiredtiger/test/suite/test_prepare_hs04.py
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+#!/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.
+
+from helper import copy_wiredtiger_home
+import wiredtiger, wttest
+from wtdataset import SimpleDataSet
+from wtscenario import make_scenarios
+from wiredtiger import stat
+
+def timestamp_str(t):
+    return '%x' % t
+
+# test_prepare_hs04.py
+# Read prepared updates from on-disk with ignore_prepare.
+# Committing or aborting a prepared update when there exists a tombstone for that key already.
+#
+class test_prepare_hs04(wttest.WiredTigerTestCase):
+    # Force a small cache.
+    conn_config = 'cache_size=50MB,statistics=(fast)'
+
+    # Create a small table.
+    uri = "table:test_prepare_hs04"
+
+    nsessions = 3
+    nkeys = 40
+    nrows = 100
+
+    scenarios = make_scenarios([
+        ('commit_transaction', dict(commit=True)),
+        ('rollback_transaction', dict(commit=False))
+    ])
+
+    def get_stat(self, stat):
+        stat_cursor = self.session.open_cursor('statistics:')
+        val = stat_cursor[stat][2]
+        stat_cursor.close()
+        return val
+
+    def search_keys_timestamp_and_ignore(self, ds, txn_config, expected_value, conflict=False):
+        cursor = self.session.open_cursor(self.uri)
+
+        commit_key = "C"
+        self.session.begin_transaction(txn_config)
+        for i in range(1, self.nsessions * self.nkeys):
+            key = commit_key + ds.key(self.nrows + i)
+            cursor.set_key(key)
+            if conflict == True:
+                self.assertRaisesException(wiredtiger.WiredTigerError, lambda:cursor.search(), expected_value)
+            elif expected_value == None:
+                self.assertEqual(cursor.search(), wiredtiger.WT_NOTFOUND)
+            else:
+                self.assertEqual(cursor.search(), 0)
+                self.assertEqual(cursor.get_value(), expected_value)
+        cursor.close()
+        self.session.commit_transaction()
+
+    def prepare_updates(self, ds):
+
+        # Commit some updates to get eviction and history store fired up
+        # Insert a key at timestamp 1
+        commit_key = "C"
+        commit_value = b"bbbbb" * 100
+        cursor = self.session.open_cursor(self.uri)
+        for i in range(1, self.nsessions * self.nkeys):
+            self.session.begin_transaction('isolation=snapshot')
+            key = commit_key + ds.key(self.nrows + i)
+            cursor.set_key(key)
+            cursor.set_value(commit_value)
+            self.assertEquals(cursor.insert(), 0)
+            self.session.commit_transaction('commit_timestamp=' + timestamp_str(1))
+        cursor.close()
+
+        # Call checkpoint
+        self.session.checkpoint()
+
+        cursor = self.session.open_cursor(self.uri)
+        for i in range(1, self.nsessions * self.nkeys):
+            self.session.begin_transaction('isolation=snapshot')
+            key = commit_key + ds.key(self.nrows + i)
+            cursor.set_key(key)
+            self.assertEquals(cursor.remove(), 0)
+            self.session.commit_transaction('commit_timestamp=' + timestamp_str(10))
+        cursor.close()
+
+        hs_writes_start = self.get_stat(stat.conn.cache_write_hs)
+        # Have prepared updates in multiple sessions. This should ensure writing
+        # prepared updates to the data store
+        # Insert the same key at timestamp 20, but with prepare updates.
+        sessions = [0] * self.nsessions
+        cursors = [0] * self.nsessions
+        prepare_value = b"ccccc" * 100
+        for j in range (0, self.nsessions):
+            sessions[j] = self.conn.open_session()
+            sessions[j].begin_transaction('isolation=snapshot')
+            cursors[j] = sessions[j].open_cursor(self.uri)
+            # Each session will update many consecutive keys.
+            start = (j * self.nkeys)
+            end = start + self.nkeys
+            for i in range(start, end):
+                cursors[j].set_key(commit_key + ds.key(self.nrows + i))
+                cursors[j].set_value(prepare_value)
+                self.assertEquals(cursors[j].insert(), 0)
+            sessions[j].prepare_transaction('prepare_timestamp=' + timestamp_str(20))
+
+        hs_writes = self.get_stat(stat.conn.cache_write_hs) - hs_writes_start
+
+        # Assert if not writing anything to the history store.
+        self.assertGreaterEqual(hs_writes, 0)
+
+        txn_config = 'read_timestamp=' + timestamp_str(5) + ',ignore_prepare=true'
+        # Search keys with timestamp 5, ignore_prepare=true and expect the cursor search to return 0 (key found)
+        self.search_keys_timestamp_and_ignore(ds, txn_config, commit_value)
+
+        txn_config = 'read_timestamp=' + timestamp_str(20) + ',ignore_prepare=true'
+        # Search keys with timestamp 20, ignore_prepare=true, expect the cursor to return wiredtiger.WT_NOTFOUND
+        self.search_keys_timestamp_and_ignore(ds, txn_config, None)
+
+        prepare_conflict_msg = '/conflict with a prepared update/'
+        txn_config = 'read_timestamp=' + timestamp_str(20) + ',ignore_prepare=false'
+        # Search keys with timestamp 20, ignore_prepare=false and expect the cursor the cursor search to return prepare conflict message
+        self.search_keys_timestamp_and_ignore(ds, txn_config, prepare_conflict_msg, True)
+
+        # If commit is True then commit the transactions and simulate a crash which would
+        # eventualy rollback transactions.
+        if self.commit == True:
+            # Commit the prepared_transactions with timestamp 30.
+            for j in range (0, self.nsessions):
+                sessions[j].commit_transaction(
+                    'commit_timestamp=' + timestamp_str(30) + ',durable_timestamp=' + timestamp_str(30))
+
+        self.session.checkpoint()
+
+        # Simulate a crash by copying to a new directory(RESTART).
+        copy_wiredtiger_home(".", "RESTART")
+
+        # Open the new directory.
+        self.conn = self.setUpConnectionOpen("RESTART")
+        self.session = self.setUpSessionOpen(self.conn)
+
+        # After simulating a crash, search for the keys inserted.
+
+        txn_config = 'read_timestamp=' + timestamp_str(5) + ',ignore_prepare=false'
+        # Search keys with timestamp 5, ignore_prepare=false and expect the cursor value to be commit_value.
+        self.search_keys_timestamp_and_ignore(ds, txn_config, commit_value)
+
+        txn_config = 'read_timestamp=' + timestamp_str(20) + ',ignore_prepare=true'
+        # Search keys with timestamp 20, ignore_prepare=true and expect the cursor search to return WT_NOTFOUND.
+        self.search_keys_timestamp_and_ignore(ds, txn_config, None)
+
+        txn_config = 'read_timestamp=' + timestamp_str(20) + ',ignore_prepare=false'
+        # Search keys with timestamp 20, ignore_prepare=false and expect the cursor search to return WT_NOTFOUND.
+        self.search_keys_timestamp_and_ignore(ds, txn_config, None)
+
+        # If commit is true then the commit_tramsactions was called and we will expect prepare_value.
+        if self.commit == True:
+            txn_config = 'read_timestamp=' + timestamp_str(30) + ',ignore_prepare=true'
+            # Search keys with timestamp 30, ignore_prepare=true and expect the cursor value to be prepare_value.
+            self.search_keys_timestamp_and_ignore(ds, txn_config, prepare_value)
+        else:
+            # Commit is false and we simulated a crash/restart which would have rolled-back the transactions, therefore we expect the
+            # cursor search to return WT_NOTFOUND.
+            txn_config = 'read_timestamp=' + timestamp_str(30) + ',ignore_prepare=true'
+            # Search keys with timestamp 30, ignore_prepare=true and expect the cursor value to return WT_NOTFOUND.
+            self.search_keys_timestamp_and_ignore(ds, txn_config, None)
+
+        if self.commit == True:
+            txn_config = 'read_timestamp=' + timestamp_str(30) + ',ignore_prepare=false'
+            # Search keys with timestamp 30, ignore_prepare=false and expect the cursor value to be prepare_value.
+            self.search_keys_timestamp_and_ignore(ds, txn_config, prepare_value)
+        else:
+            # Commit is false and we simulated a crash/restart which would have rolled-back the transactions, therefore we expect the
+            # cursor search to return WT_NOTFOUND.
+            txn_config = 'read_timestamp=' + timestamp_str(30) + ',ignore_prepare=false'
+            # Search keys with timestamp 30, ignore_prepare=false and expect the cursor value to return WT_NOTFOUND.
+            self.search_keys_timestamp_and_ignore(ds, txn_config, None)
+
+    def test_prepare_hs(self):
+
+        ds = SimpleDataSet(self, self.uri, self.nrows, key_format="S", value_format='u')
+        ds.populate()
+        bigvalue = b"aaaaa" * 100
+
+        # Initially load huge data
+        cursor = self.session.open_cursor(self.uri)
+        for i in range(1, 10000):
+            cursor.set_key(ds.key(self.nrows + i))
+            cursor.set_value(bigvalue)
+            self.assertEquals(cursor.insert(), 0)
+        cursor.close()
+        self.session.checkpoint()
+
+        # We put prepared updates in multiple sessions so that we do not hang
+        # because of cache being full with uncommitted updates.
+        self.prepare_updates(ds)
+
+if __name__ == '__main__':
+    wttest.run()