Write documentation for local testing

Author: strtgbb

tests/README.md

@@ -1 +1,75 @@
-Find CI documents and instructions on running CI checks locally [here](https://clickhouse.com/docs/development/continuous-integration).
+# Local Testing
+
+Upstream provides a utility `praktika`, which is used to run tests both locally and in CI.
+
+## Stateless
+
+### Suite
+
+Fast Test is self-contained and can be run with no extra setup.
+```sh
+python -m ci.praktika run "Fast test"
+```
+
+The stateless suites expect an executable `clickhouse` binary in `ci/tmp`
+I recommend not running suites with the `s3 storage` option as that requires extra setup.
+```sh
+python -m ci.praktika run "Stateless tests (amd_debug, sequential)"
+```
+
+### One Test
+
+Running a single test can be done with bare `clickhouse-test` or with the `praktika` utility.
+
+#### clickhouse-test
+
+https://clickhouse.com/docs/development/tests#running-a-test-locally
+
+Start Clickhouse server,
+
+```sh
+cd ci/tmp
+./clickhouse server
+```
+
+then, in another window:
+
+```sh
+tests/clickhouse-test -b ci/tmp/clickhouse 03222_pr_asan_index_granularity
+```
+
+#### praktika
+
+```sh
+python -m ci.praktika run "Stateless tests (amd_debug, sequential)" --test 01107_atomic_db_detach_attach
+```
+
+You must specify the name of a job from the PR workflow to instruct praktika on the necessary configuration.
+
+## Integration
+
+### Suite
+
+https://github.com/ClickHouse/ClickHouse/blob/master/tests/integration/README.md
+
+> The runner searches in this order and uses the first found:
+> ./ci/tmp/clickhouse
+> ./build/programs/clickhouse
+> ./clickhouse
+
+```sh
+python -m ci.praktika run "Integration tests (amd_binary, 4/5)"
+```
+
+### One Test
+
+```sh
+cd tests/integration
+./runner --docker-image-version 72c567235d2f7658765b --docker-compose-images-tags=altinityinfra/integration-test:9c789665fa1f2c3b60a8 --binary ../../ci/tmp/clickhouse 'test_storage_hudi/test.py::test_types'
+```
+
+Docker images may or may not need to be specified. Get the tags by examining ci logs.
+Search logs for `integration-test`, look for `"altinityinfra/integration-tests-runner": "72c567235d2f7658765b"`
+and `"altinityinfra/integration-test": "9c789665fa1f2c3b60a8"`
+
+Note: `runner` has been removed from 25.9 onwards.