title: "container_requests"
...
+{% comment %}
+Copyright (C) The Arvados Authors. All rights reserved.
+
+SPDX-License-Identifier: CC-BY-SA-3.0
+{% endcomment %}
API endpoint base: @https://{{ site.arvados_api_host }}/arvados/v1/container_requests@
|environment|hash|Environment variables and values that should be set in the container environment (@docker run --env@). This augments and (when conflicts exist) overrides environment variables given in the image's Dockerfile.||
|cwd|string|Initial working directory, given as an absolute path (in the container) or a path relative to the WORKDIR given in the image's Dockerfile.|Required.|
|command|array of strings|Command to execute in the container.|Required. e.g., @["echo","hello"]@|
-|output_path|string|Path to a directory or file inside the container that should be preserved as container's output when it finishes. This path must be, or be inside, one of the mount targets. For best performance, point output_path to a writable collection mount.|Required.|
+|output_path|string|Path to a directory or file inside the container that should be preserved as container's output when it finishes. This path must be, or be inside, one of the mount targets. For best performance, point output_path to a writable collection mount. Also, see "Pre-populate output using Mount points":#pre-populate-output for details regarding optional output pre-population using mount points.|Required.|
+|output_name|string|Desired name for the output collection. If null, a name will be assigned automatically.||
+|output_ttl|integer|Desired lifetime for the output collection, in seconds. If zero, the output collection will not be deleted automatically.||
|priority|integer|Higher value means spend more resources on this container_request, i.e., go ahead of other queued containers, bring up more nodes etc.|Priority 0 means a container should not be run on behalf of this request. Clients are expected to submit container requests with zero priority in order to preview the container that will be used to satisfy it. Priority can be null if and only if state!="Committed".|
|expires_at|datetime|After this time, priority is considered to be zero.|Not yet implemented.|
|use_existing|boolean|If possible, use an existing (non-failed) container to satisfy the request instead of creating a new one.|Default is true|
h2(#container_reuse). Container reuse
-When a container request is "Committed", the system will try to find and reuse any preexisting Container with the same exact command, cwd, environment, output_path, container_image, mounts, and runtime_constraints as this container request. The serialized fields environment, mounts and runtime_constraints are sorted to facilitate comparison.
+When a container request is "Committed", the system will try to find and reuse an existing Container with the same command, cwd, environment, output_path, container_image, mounts, and runtime_constraints being requested. (Hashes in the serialized fields environment, mounts and runtime_constraints are compared without regard to key order.)
-The system will use the following scheme to determine which Container to consider for reuse: A Container with the same exact command, cwd, environment, output_path, container_image, mounts, and runtime_constraints as this container request and,
-* The oldest successfully finished container, i.e., in state "Complete" with exit_code of 0. If matching containers with different outputs are found, the system will forgo reusing any of these finished containers and instead look for suitable containers in other states
-* The oldest "Running" container with the highest progress, i.e., the container that is most likely to finish first
-* The oldest "Locked" container with the highest priority, i.e., the container that is most likely to start first
-* The oldest "Queued" container with the highest priority, i.e, the container that is most likely to start first
+In order of preference, the system will use:
+* The first matching container to have finished successfully (i.e., reached state "Complete" with an exit_code of 0) whose log and output collections are still available.
+* The oldest matching "Running" container with the highest progress, i.e., the container that is most likely to finish first.
+* The oldest matching "Locked" container with the highest priority, i.e., the container that is most likely to start first.
+* The oldest matching "Queued" container with the highest priority, i.e,, the container that is most likely to start first.
+* A new container.
h2(#cancel_container). Canceling a container request
-A container request may be canceled by setting it's priority to 0, using an update call.
+A container request may be canceled by setting its priority to 0, using an update call.
When a container request is canceled, it will still reflect the state of the Container it is associated with via the container_uuid attribute. If that Container is being reused by any other container_requests that are still active, i.e., not yet canceled, that Container may continue to run or be scheduled to run by the system in future. However, if no other container_requests are using that Contianer, then the Container will get canceled as well.
projects / arvados.git / blobdiff