Profiles / #1

Passed Run of Oct 18, 15:53

CI github-actions:test · 78a4357 main dirty · pass/fail report

Some tests got too few samples to explain their time. Rerun with pytest --flakytest-profile --flakytest-rate 1000.

Wall time

32.33 s

1 worker

Test time

26.31 s

sum of test durations

Tests

225

225 passed

Profiler

py-spy

500 Hz · 11,074 samples · Python 3.14.8 · flakytest 2026.0b1

Peak memory

169 MB

test process

Where the time goes

Test time by category

Session timeline

Other

1.57 s

Tests

23.74 s

Startup

2.11 s

Collection

270 ms

Between tests

3.95 s

Session teardown

532 ms

Test phases

Setup 5.70 s Call 20.47 s Teardown 134 ms

Fix next

Ranked by the time each fix saves per run

Run tests in parallel on all 2 CPUs

Tests run one at a time: 26.3s of test time on a 2-CPU machine. With pytest-xdist this could take about 13.2s.

High Parallelism

13.15 s per run

Fix: pip install pytest-xdist, then run pytest -n auto (add it to addopts, or only in CI). pytest-django creates a separate test database per worker automatically.

Details

Tests must not share state: files in fixed paths, ports, a shared database without per-worker names, or module globals. Run with -p randomly first to shake out order dependencies.

Documentation

Use plain static file storage in tests

Static file storage/manifest handling costs 11.3s.

High App code

11.31 s per run

Fix: In test settings use STORAGES["staticfiles"] = {"BACKEND": "django.contrib.staticfiles.storage.StaticFilesStorage"} so templates don't need a manifest.

Details

Where:

apps/mcp/tests.py:66 post · 712 ms
ft/tests.py:205 test_change_password · 599 ms
apps/api/tests.py:487 upload · 470 ms
apps/orgs/tests.py:30 test_signing_up_creates_an_organization · 382 ms
ft/tests.py:200 test_change_password · 328 ms
ft/tests.py:161 test_signup · 320 ms
apps/projects/urls.py:634 <module> · 231 ms
apps/api/urls.py:72 wrapped_view · 216 ms
apps/projects/tests.py:146 test_not_logged_in · 202 ms
apps/projects/tests.py:973 test_dashboard_public_by_slug · 199 ms

Most affected tests:

ft/tests.py::TestAccountSettings::test_change_password
apps/orgs/tests.py::SignupTest::test_signing_up_creates_an_organization
ft/tests.py::TestAccountPages::test_signup
apps/projects/tests.py::ProjectPagesTest::test_dashboard_filters
apps/api/tests.py::TestApiIndex::test_index
apps/projects/tests.py::ProjectPagesTest::test_dashboard_public_by_slug
apps/api/tests.py::ProfileUploadTest::test_missing_parts_mark_the_profile_incomplete
apps/projects/tests.py::ProjectEditPage::test_not_logged_in

Disable django-debug-toolbar in tests

django-debug-toolbar is installed in the test settings and costs 6.7s.

High App code

6.69 s per run

Fix: Only add debug_toolbar to INSTALLED_APPS and MIDDLEWARE when not testing (e.g. `if DEBUG and not TESTING:`).

Details

Where:

ft/tests.py:205 test_change_password · 599 ms
apps/orgs/tests.py:30 test_signing_up_creates_an_organization · 367 ms
ft/tests.py:200 test_change_password · 328 ms
ft/tests.py:161 test_signup · 320 ms
apps/projects/urls.py:634 <module> · 231 ms
apps/api/urls.py:72 wrapped_view · 216 ms
apps/projects/urls.py:508 project_profile · 198 ms
apps/orgs/views.py:32 org_shell · 184 ms
apps/api/urls.py:59 touch_token · 127 ms
apps/projects/urls.py:50 find_project · 127 ms

Most affected tests:

ft/tests.py::TestAccountSettings::test_change_password
apps/orgs/tests.py::SignupTest::test_signing_up_creates_an_organization
ft/tests.py::TestAccountPages::test_signup
apps/projects/tests.py::ProjectPagesTest::test_dashboard_filters
apps/api/tests.py::TestApiIndex::test_index
apps/api/tests.py::ProfileUploadTest::test_missing_parts_mark_the_profile_incomplete
apps/projects/tests.py::ProjectPagesTest::test_dashboard
apps/projects/tests.py::ProfilePagePaginationTest::test_slowest_tests_first_then_the_next_page

Documentation

Repeated queries (N+1) in the code under test

25 tests run the same query 10+ times, e.g. 180x in test_seed_demo. N+1 queries slow the tests and production alike.

High Database

3.24 s per run

Fix: Django: fetch related rows in one query with select_related() for foreign keys and prefetch_related() for reverse/many-to-many relations, then lock the count in with assertNumQueries (or pytest-django's django_assert_num_queries).

Details

This changes application code, so it speeds up production too; the tests stay as they are.

180x in test_seed_demo: SELECT "projects_test"."id", "projects_test"."name", "projects_test"."project_id", "projects_test"."slug", "projects_test"."date_last_run", "projects_test"."date_first_seen", "projects_test"."first_commit_id", "projects_test"."muted" FROM "projects_test" WHERE ("projects_test"."name" = %s AND "proj…
22x in test_dashboard_filters: SELECT "projects_environment"."id", "projects_environment"."project_id", "projects_environment"."name", "projects_environment"."kind", "projects_environment"."provider", "projects_environment"."details", "projects_environment"."date_first_seen", "projects_environment"."date_last_seen" FROM "project…
21x in test_configure_page: SELECT "projects_profile"."id", "projects_profile"."project_id", "projects_profile"."number", "projects_profile"."environment_id", "projects_profile"."session_id", "projects_profile"."run_id", "projects_profile"."commit_id", "projects_profile"."ingest_id", "projects_profile"."external_id", "project…
20x in test_index: SELECT "django_content_type"."model" AS "model" FROM "django_content_type" WHERE "django_content_type"."app_label" = %s
20x in test_daily_stats_count_a_profile_once_every_part_is_in: SELECT "projects_profilepart"."id", "projects_profilepart"."profile_id", "projects_profilepart"."index", "projects_profilepart"."count", "projects_profilepart"."checksum", "projects_profilepart"."status", "projects_profilepart"."error", "projects_profilepart"."tests_count", "projects_profilepart"."…

Most affected tests:

apps/projects/tests.py::SeedDemoCommandTest::test_seed_demo
apps/projects/tests.py::ProjectPagesTest::test_dashboard_filters
apps/projects/tests.py::ProjectPagesTest::test_configure_page
apps/api/tests.py::TestApiIndex::test_index
apps/api/tests.py::ProfileUploadTest::test_daily_stats_count_a_profile_once_every_part_is_in
apps/api/tests.py::IngestStartEndpointTest::test_all_test_status_types
apps/api/tests.py::IngestStartEndpointTest::test_details_are_kept_for_failures_only
apps/api/tests.py::IngestStartEndpointTest::test_ingest_end_after_progress

Documentation

Make the test database server skip durability work

Tests spend 15.9s (60%) in the database. Test databases don't need to survive a crash, so the server can skip flushing to disk.

High Database

3.17 s per run

Fix: For a PostgreSQL test server (Docker/CI service) start it with -c fsync=off -c synchronous_commit=off -c full_page_writes=off, and put its data directory on tmpfs; for MySQL use --innodb-flush-log-at-trx-commit=0 --skip-log-bin. Never on a server with data you need.

Details

Only affects crash safety of the throwaway test server; query behaviour is identical.

Where:

apps/projects/models.py:466 save · 348 ms
apps/projects/profiles.py:313 write_snapshots · 258 ms
apps/api/tests.py:76 join_workers · 238 ms
apps/projects/tests.py:952 setUp · 220 ms
apps/api/urls.py:72 wrapped_view · 216 ms
apps/orgs/views.py:32 org_shell · 184 ms
apps/projects/profiles.py:455 write_perfs · 183 ms
apps/api/tests.py:73 setUp · 176 ms
apps/projects/models.py:35 next_number · 156 ms
apps/projects/profiles.py:358 claim_part · 146 ms

Most affected tests:

apps/api/tests.py::TestApiIndex::test_index
apps/projects/tests.py::SeedDemoCommandTest::test_seed_demo
apps/projects/tests.py::ProfilePagePaginationTest::test_slowest_tests_first_then_the_next_page
apps/projects/tests.py::ProjectPagesTest::test_configure_page
apps/api/tests.py::ProfileUploadQueueTest::test_upload_is_processed_by_the_worker
apps/api/tests.py::IngestStartEndpointTest::test_results_are_counted_and_the_payload_dropped
apps/api/tests.py::IngestStartEndpointTest::test_ingest_progress_before_start
apps/api/tests.py::IngestStartEndpointTest::test_all_test_status_types

Documentation

Stop re-running migrations on every test run

Migrations take 2.8s per run, before the first test can start.

Medium Migrations

2.56 s per run

Fix: Run with --reuse-db (add it to addopts in pytest.ini/pyproject) so the test database survives between runs; pass --create-db when migrations change. If no test depends on data migrations, --nomigrations builds the schema straight from the models, which is faster still.

Details

CI should still build the database from scratch (no --reuse-db) so broken migrations are caught.

Where:

apps/projects/migrations/0012_backfill_session_environments.py:30 backfill · 6 ms
apps/projects/migrations/0016_profile_parts.py:9 move_documents · 6 ms
apps/projects/migrations/0014_backfill_session_counts.py:23 backfill · 6 ms
apps/projects/migrations/0025_backfill_slugs_and_numbers.py:35 forwards · 3 ms
apps/projects/migrations/0015_store_compressed_documents_as_is.py:12 external_storage · 3 ms
apps/projects/migrations/0025_backfill_slugs_and_numbers.py:29 forwards · 3 ms

Most affected tests:

apps/api/tests.py::TestApiIndex::test_index

Documentation

Use a fast password hasher in tests

2.6s (10% of test time) is spent hashing passwords. Slow hashing protects real passwords; in tests it only burns CPU.

Medium Password hashing

2.48 s per run

Fix: In your test settings set PASSWORD_HASHERS = ["django.contrib.auth.hashers.MD5PasswordHasher"] (currently PBKDF2PasswordHasher).

Details

Only change the hasher in test settings. Tests that assert on a specific hash format need updating.

Where:

ft/tests.py:205 test_change_password · 597 ms
apps/orgs/tests.py:30 test_signing_up_creates_an_organization · 328 ms
ft/tests.py:200 test_change_password · 326 ms
ft/tests.py:161 test_signup · 309 ms
ft/tests.py:230 test_projects_only_lists_your_own_even_for_superusers · 271 ms
apps/orgs/tests.py:194 test_superusers_can_open_any_project_but_dont_list_them · 266 ms
ft/tests.py:213 test_change_password · 255 ms
ft/tests.py:175 setUpTestData · 255 ms

Most affected tests:

ft/tests.py::TestAccountSettings::test_change_password
apps/orgs/tests.py::SignupTest::test_signing_up_creates_an_organization
ft/tests.py::TestAccountPages::test_signup
ft/tests.py::TestAccountSettings::test_projects_only_lists_your_own_even_for_superusers
apps/orgs/tests.py::SuperuserTest::test_superusers_can_open_any_project_but_dont_list_them

Documentation

Use TestCase instead of TransactionTestCase

1.2s goes to flushing every table after tests in 11 TransactionTestCase / transaction=True / live_server tests.

Medium DB schema

1.12 s per run

Fix: Use django.test.TestCase (or @pytest.mark.django_db without transaction=True): it wraps each test in a transaction and rolls back instead of truncating every table. Keep TransactionTestCase only for tests that need real commits (on_commit hooks can use TestCase.captureOnCommitCallbacks).

Details

Tests that rely on commit behaviour, multiple connections or a live server still need a transactional test case.

Most affected tests:

apps/api/tests.py::IngestStartEndpointTest::test_ingest_valid
apps/api/tests.py::IngestStartEndpointTest::test_ingest_multiple_sessions
apps/api/tests.py::IngestStartEndpointTest::test_ingest_progress_before_start
apps/api/tests.py::ProfileUploadLockTest::test_upload_while_a_part_is_being_processed
apps/api/tests.py::IngestStartEndpointTest::test_ingest_start_progress_end
apps/api/tests.py::IngestStartEndpointTest::test_ingest_end_after_progress
apps/api/tests.py::IngestStartEndpointTest::test_results_are_counted_and_the_payload_dropped
apps/api/tests.py::IngestStartEndpointTest::test_details_are_kept_for_failures_only

Documentation

Tests open new database connections over and over

Connecting to the database takes 1.3s.

Medium Database

1.08 s per run

Fix: Reuse connections: create the engine once per session (not per test) and keep the default pool (NullPool reconnects on every checkout); in Django avoid closing connections in tests (connection.close()/close_old_connections).

Details

Where:

apps/api/tests.py:76 join_workers · 206 ms
apps/api/tests.py:73 setUp · 114 ms
apps/api/tasks.py:266 warm_reports · 70 ms
apps/api/urls.py:72 wrapped_view · 53 ms
apps/api/tests.py:212 test_ingest_start_progress_end · 34 ms
apps/api/tests.py:306 test_details_are_kept_for_failures_only · 25 ms
apps/api/tests.py:928 setUp · 24 ms
apps/api/tests.py:941 test_upload_is_processed_by_the_worker · 24 ms
apps/api/tests.py:287 test_all_test_status_types · 22 ms
apps/api/tests.py:257 test_ingest_end_after_progress · 22 ms

Most affected tests:

ft/tests.py::TestChangelogPage::test_changelog
apps/api/tests.py::IngestStartEndpointTest::test_all_test_status_types
apps/api/tests.py::IngestStartEndpointTest::test_results_are_counted_and_the_payload_dropped
apps/api/tests.py::IngestStartEndpointTest::test_ingest_start_progress_end
apps/api/tests.py::IngestStartEndpointTest::test_ingest_end_after_progress
apps/api/tests.py::IngestStartEndpointTest::test_ingest_progress_before_start
apps/api/tests.py::ProfileUploadQueueTest::test_upload_is_processed_by_the_worker
apps/api/tests.py::IngestStartEndpointTest::test_details_are_kept_for_failures_only

Create shared test data in setUpTestData instead of setUp

setUp() runs before every test and takes 844ms in total (db 777ms, library 39ms, factories 20ms) in 13 classes: SettingsTest (3 tests), ProjectsPageTest (5 tests), ProjectEditPage (6 tests), ProjectDeletePage (4 tests).

Low Database

591 ms per run

Fix: Move object creation that tests only read from setUp() into `@classmethod def setUpTestData(cls)`: it runs once per class and each test still sees the original rows (TestCase rolls back to a savepoint).

Details

Since Django 3.2 attributes assigned in setUpTestData are deep-copied per test, so in-memory changes don't leak between tests. Keep objects a test modifies in the database (or re-fetches) as before.

Where:

apps/projects/tests.py:952 setUp · 241 ms
apps/api/tests.py:73 setUp · 193 ms
apps/projects/tests.py:1374 setUp · 62 ms
apps/projects/tests.py:217 setUp · 54 ms
apps/projects/tests.py:336 setUp · 43 ms
ft/tests.py:179 setUp · 41 ms
apps/projects/tests.py:141 setUp · 40 ms
apps/projects/tests.py:99 setUp · 34 ms
apps/projects/tests.py:267 setUp · 32 ms
apps/projects/tests.py:186 setUp · 31 ms

Most affected tests:

apps/api/tests.py::IngestStartEndpointTest::test_results_are_counted_and_the_payload_dropped
apps/api/tests.py::ProfileUploadQueueTest::test_upload_is_processed_by_the_worker
apps/api/tests.py::IngestStartEndpointTest::test_ingest_progress_before_start
apps/api/tests.py::IngestStartEndpointTest::test_details_are_kept_for_failures_only
apps/api/tests.py::IngestStartEndpointTest::test_ingest_end_after_progress
ft/tests.py::TestAccountSettings::test_set_password_for_github_users
apps/projects/tests.py::ProjectPagesTest::test_test_page
apps/projects/tests.py::ProjectPagesTest::test_pending_profile_page

Documentation

Tests

201–225 of 225, slowest first · click a column to sort this page

Test	Outcome	Duration	Setup	Call	Teardown	Mostly	Queries
apps/projects/tests.py::ClassifyStreaksTest::test_dirty_runs_are_not_the_same_commit	passed	13 ms	11 ms	2 ms	0.14 ms	Database	5
apps/projects/tests.py::AnalyticsTest::test_compare_environments	passed	13 ms	0.76 ms	12 ms	0.23 ms	Libraries	11
apps/projects/tests.py::FlakyReportTest::test_single_test	passed	12 ms	0.72 ms	12 ms	0.20 ms	Database	11
apps/projects/tests.py::StorageTest::test_slow_tests_come_from_daily_stats	passed	12 ms	0.75 ms	11 ms	0.18 ms	Database	11
apps/projects/tests.py::AnalyticsTest::test_slow_tests	passed	10 ms	0.68 ms	10 ms	0.17 ms	Unsampled	10
apps/projects/tests.py::AnalyticsTest::test_resolve_scope	passed	10 ms	0.70 ms	9 ms	0.17 ms	Database	11 6 repeated
apps/projects/tests.py::RealProfileDocumentTest::test_entry_details	passed	10 ms	0.83 ms	8 ms	0.48 ms	Database	5
apps/projects/tests.py::AnalyticsTest::test_fix_next	passed	9 ms	0.69 ms	8 ms	0.19 ms	Database	8
apps/projects/tests.py::StorageTest::test_snapshot_renders_like_the_whole_document	passed	9 ms	0.72 ms	7 ms	0.72 ms	Database	9
apps/projects/tests.py::AnalyticsTest::test_environment_rows	passed	8 ms	0.80 ms	7 ms	0.18 ms	Database	8
apps/projects/tests.py::StorageTest::test_daily_stats_sum_the_days_results	passed	8 ms	0.73 ms	7 ms	0.18 ms	Database	8
apps/projects/tests.py::AnalyticsTest::test_ci_vs_local_needs_both	passed	7 ms	0.73 ms	7 ms	0.18 ms	Unsampled	9
apps/projects/tests.py::AnalyticsTest::test_suite_trend	passed	7 ms	0.63 ms	5 ms	0.65 ms	Database	6
apps/projects/tests.py::RealProfileDocumentTest::test_flat_stacks_still_work	passed	5 ms	0.90 ms	4 ms	0.16 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_environment_kinds_are_counted	passed	3 ms	0.69 ms	2 ms	0.14 ms	Database	5
apps/projects/tests.py::ClassifyStreaksTest::test_test_changed_when_the_test_file_changed	passed	3 ms	0.61 ms	2 ms	0.47 ms	pytest	5
apps/projects/tests.py::SlugsAndNumbersTest::test_test_slugs_read_like_their_node_ids	passed	3 ms	0.75 ms	2 ms	0.14 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_multiple_streaks_in_order	passed	2 ms	0.65 ms	2 ms	0.14 ms	Database	5
apps/projects/tests.py::ClassifyStreaksTest::test_flaky_even_if_the_pass_came_first_and_elsewhere	passed	2 ms	0.70 ms	1 ms	0.13 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_flaky_when_failed_and_passed_on_same_commit	passed	2 ms	0.59 ms	2 ms	0.13 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_resolved_without_changed_files	passed	2 ms	0.63 ms	1 ms	0.14 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_regression_caught_when_app_code_fixed_it	passed	2 ms	0.60 ms	1 ms	0.12 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_test_changed_matches_paths_relative_to_the_repository	passed	2 ms	0.65 ms	1 ms	0.14 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_ongoing	passed	2 ms	0.66 ms	1 ms	0.12 ms	Unsampled	5
apps/projects/tests.py::ClassifyStreaksTest::test_no_failures	passed	2 ms	0.63 ms	1 ms	0.12 ms	Unsampled	5

Page 2 of 2 Previous

Memory

The test process peaked at 195 MB

Needed the most memory	Needed	Kept after
apps/api/tests.py::TestApiIndex::test_index	35 MB	35 MB
apps/projects/tests.py::ProfilePagePaginationTest::test_slowest_tests_first_then_the_next_page	3 MB	3 MB
apps/projects/tests.py::RealProfileDocumentTest::test_call_tree	2 MB	2 MB
apps/api/tests.py::ProfileUploadTest::test_missing_parts_mark_the_profile_incomplete	1 MB	1 MB
apps/orgs/tests.py::SuperuserTest::test_superusers_can_open_any_project_but_dont_list_them	1 MB	1 MB
apps/projects/tests.py::ProjectPagesTest::test_configure_page	1 MB	1 MB
apps/projects/tests.py::ProjectPagesTest::test_dashboard_filters	1008 KB	1008 KB
apps/orgs/tests.py::SignupTest::test_signing_up_creates_an_organization	996 KB	996 KB
apps/projects/tests.py::ProjectTestsPage::test_not_logged_in	884 KB	884 KB
apps/projects/tests.py::ProjectTestsPage::test_other_peoples_project	840 KB	840 KB

Slowest fixtures

Exact setup time across the session

Fixture	Scope	Calls	Total	Max
_django_setup_unittest	class	48	3.18 s	3.16 s
django_db_setup	session	1	3.16 s	3.16 s
_unittest_setUpClass_fixture_ProjectPagesTest	class	1	305 ms	305 ms
_unittest_setUpClass_fixture_TestAccountSettings	class	1	260 ms	260 ms
_unittest_setUpClass_fixture_ProfilePagePaginationTest	class	1	235 ms	235 ms
_unittest_setUpClass_fixture_McpTest	class	1	218 ms	218 ms
_unittest_setUpClass_fixture_AnalyticsTest	class	1	190 ms	190 ms
_unittest_setUpClass_fixture_TestChangelogPage	class	1	172 ms	172 ms
_unittest_setUpClass_fixture_RealProfileDocumentTest	class	1	145 ms	145 ms
_unittest_setUpClass_fixture_MemoryTest	class	1	94 ms	94 ms
_unittest_setUpClass_fixture_StorageTest	class	1	88 ms	88 ms
_unittest_setUpClass_fixture_FlakyReportTest	class	1	74 ms	74 ms
_unittest_setUpClass_fixture_LegacyUrlTest	class	1	68 ms	68 ms
_unittest_setUpClass_fixture_FlakyReportCacheTest	class	1	55 ms	55 ms
_unittest_setUpClass_fixture_ProjectTestsPage	class	1	23 ms	23 ms