wjddn279 commented on code in PR #58365: URL: https://github.com/apache/airflow/pull/58365#discussion_r2549244321
########## airflow-core/src/airflow/utils/gc_utils.py: ########## @@ -0,0 +1,44 @@ +# +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. +from __future__ import annotations + +import gc +from functools import wraps + + +def with_gc_freeze(func): + """ + Freeze the GC before executing the function and unfreeze it after execution. + + This is done to prevent memory increase due to COW (Copy-on-Write) by moving all + existing objects to the permanent generation before forking the process. After the + function executes, unfreeze is called to ensure there is no impact on gc operations + in the original running process. Review Comment: @ashb This can be implemented as shown in https://github.com/wjddn279/airflow/commit/94810a36b0a8ea886ff511d50564a621f0b55d05. For the scheduler, gc.enable() is called after the executor starts, while for other components, gc.enable() is called during the __init__ process. I compared memory usage between implementations with and without gc.disable() using this approach. Both versions were deployed simultaneously via Docker and have been running for approximately 18 hours. | AS-IS | TO-BE | |-------|-------| | <img width="671" height="785" alt="image" src="https://github.com/user-attachments/assets/113dc477-e34c-429c-8c51-8fdebe0be5eb"; /> | <img width="644" height="807" alt="image" src="https://github.com/user-attachments/assets/d0e93f7a-7108-4432-97bc-989251ae4b08"; />| The experimental results showed virtually no memory difference between the two. While applying gc.disable() can provide benefits by preventing COW due to memory holes, I confirmed that COW did not occur even without it (even during the execution of 566,000 tasks). @potiuk Of course, COW is theoretically possible and could be observed in the future. However, given the current low probability of actual occurrence and considering the side effects of gc.disable(), I believe we should simply acknowledge the possibility for now and consider implementation only if many observed cases are reported. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
