每当我在cassandra的表中插入超过1000个数据并按id获取数据时，它会抛出以下异常：
com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: localhost/127.0.0.1:9042 (com.datastax.driver.core.exceptions.BusyPoolException: [localhost/127.0.0.1] Pool is busy (no available connection and the queue has reached its max size 256)))
at com.datastax.driver.core.RequestHandler.reportNoMoreHosts(RequestHandler.java:213)
at com.datastax.driver.core.RequestHandler.access$1000(RequestHandler.java:49)
at com.datastax.driver.core.RequestHandler$SpeculativeExecution.findNextHostAndQuery(RequestHandler.java:277)
at com.datastax.driver.core.RequestHandler$SpeculativeExecution$1.onFailure(RequestHandler.java:340)
at com.google.common.util.concurrent.Futures$6.run(Futures.java:1764)
at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:456)
at com.google.common.util.concurrent.Futures$ImmediateFuture.addListener(Futures.java:153)
at com.google.common.util.concurrent.Futures.addCallback(Futures.java:1776)
at com.google.common.util.concurrent.Futures.addCallback(Futures.java:1713)
at com.datastax.driver.core.RequestHandler$SpeculativeExecution.query(RequestHandler.java:299)
at com.datastax.driver.core.RequestHandler$SpeculativeExecution.findNextHostAndQuery(RequestHandler.java:274)
at com.datastax.driver.core.RequestHandler.startNewExecution(RequestHandler.java:117)
at com.datastax.driver.core.RequestHandler.sendRequest(RequestHandler.java:97)
at com.datastax.driver.core.SessionManager.executeAsync(SessionManager.java:132)
at com.outworkers.phantom.builder.query.CassandraOperations$class.scalaQueryStringToPromise(CassandraOperations.scala:67)
at com.outworkers.phantom.builder.query.InsertQuery.scalaQueryStringToPromise(InsertQuery.scala:31)
at com.outworkers.phantom.builder.query.CassandraOperations$class.scalaQueryStringExecuteToFuture(CassandraOperations.scala:31)
at com.outworkers.phantom.builder.query.InsertQuery.scalaQueryStringExecuteToFuture(InsertQuery.scala:31)
at com.outworkers.phantom.builder.query.ExecutableStatement$class.future(ExecutableQuery.scala:80)
at com.outworkers.phantom.builder.query.InsertQuery.future(InsertQuery.scala:31)
at nd.cluster.data.store.Points.upsert(Models.scala:114)我已经用pooligoptions解决了上述问题。
val poolingOptions = new PoolingOptions()
.setConnectionsPerHost(HostDistance.LOCAL, 1, 200)
.setMaxRequestsPerConnection(HostDistance.LOCAL, 256)
.setNewConnectionThreshold(HostDistance.LOCAL, 100).setCoreConnectionsPerHost(HostDistance.LOCAL, 200)
val builder1 = ContactPoint.local
.noHeartbeat()
.withClusterBuilder(_.withoutJMXReporting()
.withoutMetrics().withPoolingOptions(poolingOptions)).keySpace("nd")现在它甚至可以使用1l数据。但我不确定它的效率。有人能帮我吗？
1条答案
按热度按时间q3aa05251#
这意味着您提交了太多的请求，而不是在提交更多请求之前等待未来完成。
每个连接的默认最大请求数为1024。如果所有连接都超过此数目，则连接池将对某些请求排队，最多256个。如果队列已满，则抛出busypoolexception。当然，您可以增加每个连接的最大请求数和每个主机的最大连接数。但真正的解决办法当然是节流你的线程。例如，您可以按1000个批次提交请求，然后等待将来完成后再提交更多请求，或者使用信号量来调节待处理请求的总数，并确保它们不超过某个数量（理论上，这个数字必须低于num\u hostsmax\u connections\u per\u hostmax\u requests\u per\u connection–实际上，我不建议超过1000，因为它可能不会为您带来更多吞吐量）。
你可能会发现这个链接很有用。
https://github.com/redisson/redisson/issues/438
https://groups.google.com/a/lists.datastax.com/forum/#!主题/java驱动程序用户/p3cwol0knrshttp://docs.datastax.com/en/developer/java-driver/3.1/manual/pooling