KahaDB访问速度慢

Question

在运行了大约3个月的activemq broker之后，它变得非常慢，如下所示。当它重新启动时，它恢复正常(大约600ms - 1000ms)。

我在找问题的原因。硬盘速度相当快，1K rpm，IOs不多。请告诉我你是否知道(能猜到)问题的原因和解决方案。

    2012-08-27 19:24:06,670 | INFO  | Slow KahaDB access: cleanup took 7190 | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Journal Checkpoint Worker
    2012-08-27 21:44:14,814 | INFO  | Slow KahaDB access: cleanup took 7176 | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Journal Checkpoint Worker
    2012-08-27 23:58:15,124 | INFO  | Slow KahaDB access: cleanup took 7210 | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Journal Checkpoint Worker
    2012-08-28 02:09:03,120 | INFO  | Slow KahaDB access: cleanup took 7212 | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Journal Checkpoint Worker
    2012-08-28 04:27:46,521 | INFO  | Slow KahaDB access: cleanup took 7196 | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Journal Checkpoint Worker
    2012-08-28 06:36:38,818 | INFO  | Slow KahaDB access: cleanup took 7191 | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Journal Checkpoint Worker
    2012-08-28 08:28:09,937 | INFO  | Slow KahaDB access: Journal append took: 13 ms, Index update took 7165 ms | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Transport: tcp:///127.0.0.1:39951
    2012-08-28 08:29:01,715 | INFO  | Slow KahaDB access: Journal append took: 18 ms, Index update took 7171 ms | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Transport: tcp:///127.0.0.1:39951
    2012-08-28 08:29:26,039 | INFO  | Slow KahaDB access: Journal append took: 30 ms, Index update took 7194 ms | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Transport: tcp:///127.0.0.1:39951
    2012-08-28 08:29:52,283 | INFO  | Slow KahaDB access: Journal append took: 7193 ms, Index update took 116 ms | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Transport: tcp:///127.0.0.1:39951
    2012-08-28 08:30:12,140 | INFO  | Slow KahaDB access: Journal append took: 0 ms, Index update took 7596 ms | org.apache.activemq.store.kahadb.MessageDatabase | ActiveMQ Transport: tcp:///127.0.0.1:39956
    2012-08-28 08:30:25,763 | INFO  | Slow KahaDB access: Journal append took: 11 ms, Index update took 7760 ms |

谢谢你们。

Answer 1

我们也遇到了同样的问题，结果是内存泄漏(对象永远不会从集合中删除)。试着运行一个java内存分析器，观察几天内内存的逐渐增长。在我们的例子中，JRockit的“任务控制”非常棒。