-
Notifications
You must be signed in to change notification settings - Fork 1.5k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Browse files
Browse the repository at this point in the history
* Add documentation on request cancellation * Include python backend * Update docs/user_guide/request_cancellation.md * Update docs/user_guide/request_cancellation.md * Update docs/README.md * Update docs/user_guide/request_cancellation.md * Remove inflight term from the main documentation * Address review comments * Fix * Update docs/user_guide/request_cancellation.md * Fix --------- Co-authored-by: Iman Tabrizian <[email protected]> Co-authored-by: Neelay Shah <[email protected]> Co-authored-by: Ryan McCormick <[email protected]> Co-authored-by: Jacky <[email protected]>
- Loading branch information
5 people
authored
Oct 11, 2023
1 parent
c7fbd3c
commit f8a78ba
Showing
2 changed files
with
104 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,101 @@ | ||
| <!-- | ||
| # Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved. | ||
| # | ||
| # Redistribution and use in source and binary forms, with or without | ||
| # modification, are permitted provided that the following conditions | ||
| # are met: | ||
| # * Redistributions of source code must retain the above copyright | ||
| # notice, this list of conditions and the following disclaimer. | ||
| # * Redistributions in binary form must reproduce the above copyright | ||
| # notice, this list of conditions and the following disclaimer in the | ||
| # documentation and/or other materials provided with the distribution. | ||
| # * Neither the name of NVIDIA CORPORATION nor the names of its | ||
| # contributors may be used to endorse or promote products derived | ||
| # from this software without specific prior written permission. | ||
| # | ||
| # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY | ||
| # EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
| # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | ||
| # PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR | ||
| # CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | ||
| # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | ||
| # PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | ||
| # PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | ||
| # OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
| # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | ||
| # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
| --> | ||
|
|
||
| # Request Cancellation | ||
|
|
||
| Starting from 23.10, Triton supports handling request cancellation received | ||
| from the gRPC client or a C API user. Long running inference requests such | ||
| as for auto generative large language models may run for an indeterminate | ||
| amount of time or indeterminate number of steps. Additionally clients may | ||
| enqueue a large number of requests as part of a sequence or request stream | ||
| and later determine the results are no longer needed. Continuing to process | ||
| requests whose results are no longer required can significantly impact server | ||
| resources. | ||
|
|
||
| ## Issuing Request Cancellation | ||
|
|
||
| ### Triton C API | ||
|
|
||
| [In-Process Triton Server C API](../customization_guide/inference_protocols.md#in-process-triton-server-api) has been enhanced with `TRITONSERVER_InferenceRequestCancel` | ||
| and `TRITONSERVER_InferenceRequestIsCancelled` to issue cancellation and query | ||
| whether cancellation has been issued on an inflight request respectively. Read more | ||
| about the APIs in [tritonserver.h](https://github.com/triton-inference-server/core/blob/main/include/triton/core/tritonserver.h). | ||
|
|
||
|
|
||
| ### gRPC Endpoint | ||
|
|
||
| In addition, [gRPC endpoint](../customization_guide/inference_protocols.md#httprest-and-grpc-protocols) can | ||
| now detect cancellation from the client and attempt to terminate request. | ||
| At present, only gRPC python client supports issuing request cancellation | ||
| to the server endpoint. See [request-cancellation](https://github.com/triton-inference-server/client#request-cancellation) | ||
| for more details on how to issue requests from the client-side. | ||
| See gRPC guide on RPC [cancellation](https://grpc.io/docs/guides/cancellation/) for | ||
| finer details. | ||
|
|
||
| ## Handling in Triton Core | ||
|
|
||
| Triton core checks for requests that have been cancelled at some critical points | ||
| when using [dynamic](./model_configuration.md#dynamic-batcher) or | ||
| [sequence](./model_configuration.md#sequence-batcher) batching. The checking is | ||
| also performed between each | ||
| [ensemble](./model_configuration.md#ensemble-scheduler) steps and terminates | ||
| further processing if the request is cancelled. | ||
|
|
||
| On detecting a cancelled request, Triton core responds with CANCELLED status. If a request | ||
| is cancelled when using [sequence_batching](./model_configuration.md#sequence-batcher), | ||
| then all the pending requests in the same sequence will also be cancelled. The sequence | ||
| is represented by the requests that has identical sequence id. | ||
|
|
||
| **Note**: Currently, Triton core does not detect cancellation status of a request once | ||
| it is forwarded to [rate limiter](./rate_limiter.md). Improving the request cancellation | ||
| detection and handling within Triton core is work in progress. | ||
|
|
||
| ## Handling in Backend | ||
|
|
||
| Upon receiving request cancellation, triton does its best to terminate request | ||
| at various points. However, once a request has been given to the backend | ||
| for execution, it is upto the individual backends to detect and handle | ||
| request termination. | ||
| Currently, the following backends support early termination: | ||
| - [vLLM backend](https://github.com/triton-inference-server/vllm_backend) | ||
| - [python backend](https://github.com/triton-inference-server/python_backend) | ||
|
|
||
| Python backend is a special case where we expose the APIs to detect cancellation | ||
| status of the request but it is up to the `model.py` developer to detect whether | ||
| the request is cancelled and terminate further execution. | ||
|
|
||
| **For the backend developer**: The backend APIs have also been enhanced to let the | ||
| backend detect whether the request received from Triton core has been cancelled. | ||
| See `TRITONBACKEND_RequestIsCancelled` and `TRITONBACKEND_ResponseFactoryIsCancelled` | ||
| in [tritonbackend.h](https://github.com/triton-inference-server/core/blob/main/include/triton/core/tritonbackend.h) | ||
| for more details. The backend upon detecting request cancellation can stop processing | ||
| it any further. | ||
| The Python models running behind Python backend can also query the cancellation status | ||
| of request and response_sender. See [this](https://github.com/triton-inference-server/python_backend#request-cancellation-handling) | ||
| section in python backend documentation for more details. | ||
|
|