wForget commented on code in PR #4232: URL: https://github.com/apache/datafusion-comet/pull/4232#discussion_r3193451304
########## common/src/main/java/org/apache/comet/udf/CometUdfBridge.java: ########## @@ -0,0 +1,141 @@ +/* + * 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. + */ + +package org.apache.comet.udf; + +import java.util.LinkedHashMap; +import java.util.Map; + +import org.apache.arrow.c.ArrowArray; +import org.apache.arrow.c.ArrowSchema; +import org.apache.arrow.c.Data; +import org.apache.arrow.memory.BufferAllocator; +import org.apache.arrow.vector.FieldVector; +import org.apache.arrow.vector.ValueVector; + +/** + * JNI entry point for native execution to invoke a {@link CometUDF}. Matches the static-method + * pattern used by CometScalarSubquery so the native side can dispatch via + * call_static_method_unchecked. + */ +public class CometUdfBridge { + + // Per-thread, bounded LRU of UDF instances keyed by class name. Comet + // native execution threads (Tokio/DataFusion worker pool) are reused + // across tasks within an executor, so the effective lifetime of cached + // entries is the worker thread (i.e. the executor JVM). This is fine for + // stateless UDFs like ArrayExistsUDF; future stateful UDFs would need + // explicit per-task isolation. + private static final int CACHE_CAPACITY = 64; + + private static final ThreadLocal<LinkedHashMap<String, CometUDF>> INSTANCES = Review Comment: Should we ensure one instance per thread? Spark/Hive UDFs don't seem to do this. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
