zhangstar333 commented on code in PR #66637: URL: https://github.com/apache/doris/pull/66637#discussion_r3818864181
########## fe/fe-core/src/main/java/org/apache/doris/datasource/lance/LanceMetadataReadExecutor.java: ########## @@ -0,0 +1,139 @@ +// 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.doris.datasource.lance; + +import org.apache.doris.common.ThreadPoolManager; +import org.apache.doris.qe.ConnectContext; + +import com.google.common.annotations.VisibleForTesting; + +import java.util.Locale; +import java.util.concurrent.Callable; +import java.util.concurrent.ExecutionException; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.Future; +import java.util.concurrent.RejectedExecutionException; +import java.util.concurrent.ThreadPoolExecutor; +import java.util.concurrent.TimeUnit; +import java.util.concurrent.TimeoutException; + +/** Runs Lance JNI metadata reads behind a finite FE concurrency and deadline boundary. */ +final class LanceMetadataReadExecutor { + private static final int DEFAULT_TIMEOUT_SECONDS = 60; + private static final int MAX_CONCURRENT_READS = 4; + private static final int MAX_QUEUED_READS = 16; + private static final ThreadPoolExecutor EXECUTOR = ThreadPoolManager.newDaemonFixedThreadPool( + MAX_CONCURRENT_READS, + MAX_QUEUED_READS, + "lance-metadata-read", + false, + new ThreadPoolExecutor.AbortPolicy()); + + private LanceMetadataReadExecutor() { + } + + static <T> T execute(Callable<T> task) throws Exception { + ConnectContext context = ConnectContext.get(); + int queryTimeoutSeconds = context == null + ? DEFAULT_TIMEOUT_SECONDS : context.getQueryTimeoutS(); + int timeoutSeconds = queryTimeoutSeconds > 0 + ? Math.min(queryTimeoutSeconds, DEFAULT_TIMEOUT_SECONDS) : DEFAULT_TIMEOUT_SECONDS; + return execute(task, EXECUTOR, timeoutSeconds, TimeUnit.SECONDS); + } + + @VisibleForTesting + static <T> T execute(Callable<T> task, ExecutorService executor, + long timeout, TimeUnit timeoutUnit) throws Exception { + if (timeout <= 0) { + throw new IllegalArgumentException("Lance metadata read timeout must be positive"); + } + long timeoutNanos = timeoutUnit.toNanos(timeout); + if (timeoutNanos <= 0) { + throw new IllegalArgumentException("Lance metadata read timeout is too small"); + } + + long deadlineNanos = System.nanoTime() + timeoutNanos; + Future<T> future; + try { + future = executor.submit(() -> { + // A request can expire while waiting in the finite queue. Do not enter JNI for a + // result whose caller has already timed out. + if (remainingNanos(deadlineNanos) <= 0) { + throw timeoutFailure(timeout, timeoutUnit); + } + return task.call(); + }); + } catch (RejectedExecutionException e) { + throw new MetadataReadCapacityException( + "Lance metadata read capacity is exhausted"); + } + + try { + long remainingNanos = remainingNanos(deadlineNanos); + if (remainingNanos <= 0) { + throw timeoutFailure(timeout, timeoutUnit); + } + return future.get(remainingNanos, TimeUnit.NANOSECONDS); + } catch (TimeoutException e) { + // Deliberately do not cancel or interrupt the Future. If JNI has started, the worker + // remains the sole owner of its Dataset and allocator until the native call returns. Review Comment: `do not cancel or interrupt the Future` Will this cause the thread pool to be exhausted, making it unusable for everyone? -- 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]
