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我使用 CQ v5.16.11（带有 openjdk 11）来保存每日滚动周期的数据。这个过程从周日到周五不间断地运行，所以我每周有 5 个 cq4 文件。我运行了 1.5 周，有 8 个文件（第 1 周 3 个，第 2 周 5 个）。

所以我拥有的文件是：

20181003.cq4 cycle=17807,
20181004.cq4 cycle=17808,
20181005.cq4 cycle=17809,
20181007.cq4 cycle=17811,
20181008.cq4 cycle=17812,
20181009.cq4 cycle=17813,
20181010.cq4 cycle=17814,
20181011.cq4 cycle=17815,

请注意 20181006.cq4 (cycle=17810) 的缺失文件，因为该过程在星期六不运行。

我使用此代码读取数据：

tailer.toEnd();
lastTailerIndex = tailer.index();
tailer.toStart();

while (tailer.index() <= lastTailerIndex) {
    // read data
    if (tailer.readBytes(data) {
     /// do something with data bytes
    }
    if (tailer.index() == lastTailerIndex) {
        break;
    }
}

这会正确读取第一周的数据，但不会读取第二周的数据，因为它不会自动滚动到下一个周期。

知道为什么会发生这种情况或如何解决这个问题吗？

这个问题与旧版本的问题类似

日志：

2018-10-12 12:41:15,784 DEBUG [main] net.openhft.chronicle.bytes.MappedFile - Allocation of 0 chunk in /site/data/metadata.cq4t took 19.237 ms.
2018-10-12 12:41:15,876 DEBUG [main] net.openhft.chronicle.bytes.MappedFile - Allocation of 0 chunk in /site/data/20181011.cq4 took 0.063 ms.
2018-10-12 12:41:15,881 DEBUG [main] net.openhft.chronicle.queue.impl.single.PretoucherState - /site/data/20181011.cq4 - Reset pretoucher to pos 4835096 as the underlying MappedBytes changed.
2018-10-12 12:41:15,887 DEBUG [main] net.openhft.chronicle.bytes.MappedFile - Allocation of 0 chunk in /site/data/20181003.cq4 took 0.065 ms.
2018-10-12 12:41:15,995 DEBUG [main] net.openhft.chronicle.bytes.MappedFile - Allocation of 0 chunk in /site/data/20181011.cq4 took 0.082 ms.
2018-10-12 12:41:15,996 DEBUG [main] net.openhft.chronicle.queue.impl.single.SingleChronicleQueueBuilder - File released /site/data/20181003.cq4
2018-10-12 12:41:15,997 DEBUG [main] net.openhft.chronicle.queue.impl.single.SingleChronicleQueueBuilder - File released /site/data/20181011.cq4
2018-10-12 12:41:16,418 DEBUG [main] net.openhft.chronicle.bytes.MappedFile - Allocation of 0 chunk in /site/data/20181004.cq4 took 0.112 ms.
2018-10-12 12:41:16,418 DEBUG [main] net.openhft.chronicle.queue.impl.single.SingleChronicleQueueBuilder - File released /site/data/20181003.cq4
2018-10-12 12:41:16,813 DEBUG [main] net.openhft.chronicle.bytes.MappedFile - Allocation of 0 chunk in /site/data/20181005.cq4 took 0.084 ms.
2018-10-12 12:41:16,813 DEBUG [main] net.openhft.chronicle.queue.impl.single.SingleChronicleQueueBuilder - File released /site/data/20181004.cq4

[编辑 1]： 上周末也发生了同样的事情，即，正如预期的那样，10 月 13 日没有新文件。现在我有 10 月 7 日到 10 月 15 日的文件（缺少 10 月 13 日的文件）。如果我这样做tailer.toStart(); while(tailer.readBytes() { ...}，它只会从 10 月 7 日到 10 月 12 日读取文件，而不会读取 10 月 14 日和 15 日的文件。

[编辑 2]：将问题复制如下 Chronicle-Queue/issues/537

  1. 设置/库： jvm openjdk 11、Ubuntu 16.04、openhft.affinity/3.1.9、chronicle-map/3.16.0、chronicle-queue/5.16.11、chronicle-bytes/1.16.23、chronicle-core/1.16.20 ，编年史线/1.16.16，编年史线程/1.16.3，jna/4.4.0
  2. 脚步：
    • 启动 WriterProcess - 让它完成。
    • 启动 ReaderProcess - 查看 5 个打印语句。
    • 停止 ReaderProcess
    • 等待一段时间 - 10 分钟。
    • 再次启动 WriterProcess - 让它完成或继续运行这个过程。
    • 启动 ReaderProcess - 它只打印前 5 个打印语句，此后不打印任何内容。即使 WriterProcess 正在运行/写入以排队，该进程中的尾部也不会向前移动。
public class WriterProcess {
        public static void main(String[] args) throws InterruptedException {
            final String dir = "/tmp/demo/";
            final LocalTime localTime = LocalTime.of(17, 0);
            final ZoneId zoneID = ZoneId.of("America/New_York");
            final ScheduledExecutorService scheduledExecutorService = Executors.newScheduledThreadPool(2);
            final SingleChronicleQueue queue  = SingleChronicleQueueBuilder.binary(dir)
                    .blockSize((long) Math.pow(2, 23))
                    .rollCycle(RollCycles.MINUTELY)
                    .rollTime(localTime, zoneID)
                    .build();
            final ExcerptAppender appender = queue.acquireAppender();
            // pre touch
            scheduledExecutorService.scheduleAtFixedRate(appender::pretouch,0,30, TimeUnit.SECONDS);
            // write data
            System.out.println("writing data ...");
            writeData(appender, 5);
            // close queue
            System.out.println("shutting down now ...");
            queue.close();
            scheduledExecutorService.shutdown();
            scheduledExecutorService.awaitTermination(1, TimeUnit.SECONDS);
        }
        public static void writeData(ExcerptAppender appender, int count) {
            int ctr = 0;
            String dateStr;
            Date date = new Date();
            while (true) {
                dateStr = date.toString();
                appender.writeText("["+ctr+"] Written " + dateStr);
                System.out.println("["+ctr+"] Written " + dateStr);
                ctr++;
                if (ctr >= count) {
                    break;
                }
                try {
                    Thread.sleep(65_000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }
    public class ReaderProcess {
        public static void main(String[] args) {
            final String dir = "/tmp/demo/";
            final LocalTime localTime = LocalTime.of(17, 0);
            final ZoneId zoneID = ZoneId.of("America/New_York");
            final SingleChronicleQueue queue  = SingleChronicleQueueBuilder.binary(dir)
                    .blockSize((long) Math.pow(2, 23))
                    .rollCycle(RollCycles.MINUTELY)
                    .rollTime(localTime, zoneID)
                    .build();
            final ExcerptTailer tailer = queue.createTailer();
            tailer.toStart();
            // read data
            System.out.println("reading data ...");
            readData(tailer, 25);
            // close
            System.out.println("shutting down now ...");
            queue.close();
        }
        public static void readData(ExcerptTailer tailer, int count) {
            int ctr = 0;
            Bytes data = Bytes.allocateDirect(new byte[500]);
            while (true) {
                if (tailer.readBytes(data)) {
                    System.out.println("["+ctr+"] Read {"+ data + "}");
                    ctr++;
                    if (ctr >= count) {
                        break;
                    }
                }
            }
        }
    }
4

1 回答 1

1

我编写了一个稍微简单的版本，它适用于 Chronicle-bom 2.17 及其使用的版本。我所做的最大更改是data在读取之前清除字节，否则它只会附加，以免覆盖任何内容。

import net.openhft.chronicle.bytes.Bytes;
import net.openhft.chronicle.core.OS;
import net.openhft.chronicle.queue.ExcerptAppender;
import net.openhft.chronicle.queue.ExcerptTailer;
import net.openhft.chronicle.queue.RollCycles;
import net.openhft.chronicle.queue.impl.single.SingleChronicleQueue;
import net.openhft.chronicle.queue.impl.single.SingleChronicleQueueBuilder;

import java.time.LocalDateTime;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

public class WriterProcess {
    static final String dir = OS.TMP + "/demo-" + System.nanoTime() + "/";

    public static void main(String[] args) throws InterruptedException {
        final ScheduledExecutorService scheduledExecutorService = Executors.newScheduledThreadPool(2);
        final SingleChronicleQueue queue = SingleChronicleQueueBuilder.binary(dir)
                .testBlockSize()
                .rollCycle(RollCycles.TEST_SECONDLY)
                .build();
        final ExcerptAppender appender = queue.acquireAppender();
        // pre touch
        scheduledExecutorService.scheduleAtFixedRate(appender::pretouch, 3, 30, TimeUnit.SECONDS);
        new Thread(ReaderProcess::main).start();
        // write data
        System.out.println("writing data ...");
        writeData(appender, 100);
        // close queue
        System.out.println("shutting down now ...");
        queue.close();
        scheduledExecutorService.shutdown();
        scheduledExecutorService.awaitTermination(1, TimeUnit.SECONDS);
    }

    public static void writeData(ExcerptAppender appender, int count) {
        int ctr = 0;
        while (true) {
            LocalDateTime date = LocalDateTime.now();
            appender.writeText("[" + ctr + "] Written " + date);
            System.out.println("[" + ctr + "] Written " + date);
            ctr++;
            if (ctr >= count) {
                break;
            }
            try {
                Thread.sleep(2_200);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

class ReaderProcess {
    public static void main(String... args) {
        final String dir = WriterProcess.dir;
        final SingleChronicleQueue queue = SingleChronicleQueueBuilder.binary(dir)
                .testBlockSize()
                .rollCycle(RollCycles.TEST_SECONDLY)
                .build();
        final ExcerptTailer tailer = queue.createTailer();
        tailer.toStart();
        // read data
        System.out.println("reading data ...");
        readData(tailer, 100);
        // close
        System.out.println("shutting down now ...");
        queue.close();
    }

    public static void readData(ExcerptTailer tailer, int count) {
        int ctr = 0;
        Bytes data = Bytes.allocateDirect(64);
        while (true) {
            data.clear();
            if (tailer.readBytes(data)) {
                System.out.println("[" + ctr + "] Read {" + data + "}");
                ctr++;
                if (ctr >= count) {
                    break;
                }
            }
        }
    }
}
于 2018-10-16T07:35:56.970 回答