Update doc

apache · Mar 29, 2022 · 9ad0ba9 · 9ad0ba9
1 parent 860c4f0
commit 9ad0ba9
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/website/www/site/content/en/documentation/sdks/python-pipeline-dependencies.md b/website/www/site/content/en/documentation/sdks/python-pipeline-dependencies.md
@@ -142,17 +142,20 @@ In pipeline execution modes where a Beam runner launches SDK workers in Docker c
 1. Provide the container engine. Beam supports `local_docker`(requires local installation of Docker) and `cloud_build`(requires a GCP project with Cloud Build API enabled).
 
        --prebuild_sdk_container_engine=<container_engine>
-2. To pass a base image for pre-building dependencies, provide `--sdk_container_image`. If not, Apache beam's base [image](https://hub.docker.com/search?q=apache%2Fbeam&type=image) would be used.
 
-       --sdk_container_image=<location_to_base_image>
-3. If using `local_docker` engine, provide a URL for the remote registry to which the image will be pushed by passing
+2. If using `local_docker` engine, provide a URL for the remote registry to which the image will be pushed by passing
 
        --docker_registry_push_url=<remote_registry_url>
        # Example: --docker_registry_push_url=<registry_name>/beam
        # pre-built image will be pushed to the <registry_name>/beam/beam_python_prebuilt_sdk:<unique_image_tag>
        # <unique_image_tag> tag is generated by Beam SDK.
 
    **NOTE:** `docker_registry_push_url` must be a remote registry.
-> To use Docker, the `--sdk_container_image` should be compatible with Apache Beam Runner. Please follow the [instructions](https://beam.apache.org/documentation/runtime/environments/#building-and-pushing-custom-containers) on how to build a base container image compatible with Apache Beam.
+> The pre-building feature requires the Apache Beam SDK for Python, version 2.25.0 or later.
+The container images created during prebuilding will persist beyond the pipeline runtime.
+Once your job is finished or stopped, you can remove the pre-built image from the container registry.
+
+>If your pipeline is using a custom container image, most likely you will not benefit from pre-building step as extra dependencies can be preinstalled in the custom image at build time. If you still would like to use pre-building with custom images, use Apache Beam SDK 2.38.0 or newer and
+ supply your custom image via `--sdk_container_image` pipeline option.
 
 **NOTE**: This feature is available only for the `Dataflow Runner v2`.