Add benchmarking test suite and greatly improve performance in a few cases (#948)

* Add benchmarking test suite

* Improve amortized time of model relation loads with a large number of rows

* Improve performance of loading models with many related models

* Improve performance of loading models with many related models to O(N)ish

* Fix bug where N model creation with shared related model would build in N^2 time

* Lower blocking time for queryset results

* Add docstrings and streamline hash code

Co-authored-by: haydeec1 <Eric.Haydel@jhuapl.edu>

benchmarks/test_benchmark_bulk_update.py

@@ -0,0 +1,27 @@
+import random
+import string
+from typing import List
+
+import pytest
+
+from benchmarks.conftest import Author
+
+pytestmark = pytest.mark.asyncio
+
+
+@pytest.mark.parametrize("num_models", [10, 20, 40])
+async def test_updating_models_in_bulk(
+    aio_benchmark, num_models: int, authors_in_db: List[Author]
+):
+    starting_first_name = authors_in_db[0].name
+
+    @aio_benchmark
+    async def update(authors: List[Author]):
+        await Author.objects.bulk_update(authors)
+
+    for author in authors_in_db:
+        author.name = "".join(random.sample(string.ascii_letters, 5))
+
+    update(authors_in_db)
+    author = await Author.objects.get(id=authors_in_db[0].id)
+    assert author.name != starting_first_name