tustvold commented on code in PR #2226: URL: https://github.com/apache/arrow-datafusion/pull/2226#discussion_r851360139
########## datafusion/scheduler/src/pipeline/execution.rs: ########## @@ -0,0 +1,324 @@ +// 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. + +use std::any::Any; +use std::collections::VecDeque; +use std::fmt::Formatter; +use std::pin::Pin; +use std::sync::Arc; +use std::task::{Context, Poll, Waker}; + +use arrow::error::ArrowError; +use async_trait::async_trait; +use futures::{Stream, StreamExt, TryStreamExt}; +use parking_lot::Mutex; + +use datafusion::arrow::datatypes::SchemaRef; +use datafusion::arrow::{error::Result as ArrowResult, record_batch::RecordBatch}; +use datafusion::error::Result; +use datafusion::execution::context::TaskContext; +use datafusion::physical_plan::expressions::PhysicalSortExpr; +use datafusion::physical_plan::metrics::MetricsSet; +use datafusion::physical_plan::{ + displayable, DisplayFormatType, Distribution, ExecutionPlan, Partitioning, + RecordBatchStream, SendableRecordBatchStream, Statistics, +}; + +use crate::pipeline::Pipeline; +use crate::BoxStream; + +/// An [`ExecutionPipeline`] wraps a portion of an [`ExecutionPlan`] and +/// converts it to the push-based [`Pipeline`] interface +/// +/// Internally [`ExecutionPipeline`] is still pull-based which limits its parallelism +/// to that of its output partitioning, however, it provides full compatibility with +/// [`ExecutionPlan`] allowing full interoperability with the existing ecosystem +/// +/// Longer term we will likely want to introduce new traits that differentiate between +/// stateless operators like filters, and stateful aggregations, and are better aligned +/// with a push-based execution model. This in turn will allow for [`Pipeline`] implementations +/// that are able to introduce parallelism beyond that expressed in their partitioning Review Comment: Yes, I shall reword to use pipeline breaker instead of stateful 👍 -- 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]
