LanceMetadataReadExecutor.java
// 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.
throw timeoutFailure(timeout, timeoutUnit);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
// As with timeout, interruption of the waiting caller must not interrupt JNI.
throw new MetadataReadInterruptedException(
"Interrupted while waiting for Lance metadata read");
} catch (ExecutionException e) {
Throwable cause = e.getCause();
if (cause instanceof Exception) {
throw (Exception) cause;
}
if (cause instanceof Error) {
throw (Error) cause;
}
throw new RuntimeException(cause);
}
}
private static long remainingNanos(long deadlineNanos) {
return deadlineNanos - System.nanoTime();
}
private static MetadataReadTimeoutException timeoutFailure(long timeout, TimeUnit timeoutUnit) {
return new MetadataReadTimeoutException("Lance metadata read timed out after "
+ timeout + " " + timeoutUnit.name().toLowerCase(Locale.ROOT));
}
static final class MetadataReadTimeoutException extends RuntimeException {
MetadataReadTimeoutException(String message) {
super(message);
}
}
static final class MetadataReadCapacityException extends RuntimeException {
MetadataReadCapacityException(String message) {
super(message);
}
}
static final class MetadataReadInterruptedException extends RuntimeException {
MetadataReadInterruptedException(String message) {
super(message);
}
}
}