为什么 rpc 超时发生在 cassandra答案

【问题标题】：why the rpc timeout occur in cassandra为什么 rpc 超时发生在 cassandra
【发布时间】：2013-12-19 15:17:43
【问题描述】：

我尝试在我的键空间上使用 cqlsh -3 版本，并在列族上使用选择查询。它在某些原因中返回数据并在某些其他原因中引发 RPC 超时，我不知道确切的根本原因。我使用带有单个 where 条件的 select 查询

select * FROM date where date='2013-10-11 00:00:00+0000';

在此日期列中具有数据类型为 UTF8 格式文本的二级索引

Request did not complete within rpc_timeout.

我检查了 cassandra log.it throws

ERROR [ReadStage:117] 2013-12-03 19:21:46,813 CassandraDaemon.java (line 192) Exception in thread Thread[ReadStage:117,5,main]
at org.apache.cassandra.db.columniterator.SSTableNamesIterator.read(SSTableNamesIterator.java:119)
at org.apache.cassandra.db.columniterator.SSTableNamesIterator.<init>(SSTableNamesIterator.java:60)
at org.apache.cassandra.db.filter.NamesQueryFilter.getSSTableColumnIterator(NamesQueryFilter.java:81)
at org.apache.cassandra.db.filter.QueryFilter.getSSTableColumnIterator(QueryFilter.java:68)
at org.apache.cassandra.db.CollationController.collectTimeOrderedData(CollationController.java:132)
at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:65)
at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:1390)
at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1213)
at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1125)
at org.apache.cassandra.db.index.keys.KeysSearcher$1.computeNext(KeysSearcher.java:191)
at org.apache.cassandra.db.index.keys.KeysSearcher$1.computeNext(KeysSearcher.java:109)
at com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143)
at com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138)
at org.apache.cassandra.db.ColumnFamilyStore.filter(ColumnFamilyStore.java:1499)
at org.apache.cassandra.db.index.keys.KeysSearcher.search(KeysSearcher.java:82)
at org.apache.cassandra.db.index.SecondaryIndexManager.search(SecondaryIndexManager.java:548)
at org.apache.cassandra.db.ColumnFamilyStore.search(ColumnFamilyStore.java:1487)
at org.apache.cassandra.service.RangeSliceVerbHandler.executeLocally(RangeSliceVerbHandler.java:44)
at org.apache.cassandra.service.StorageProxy$LocalRangeSliceRunnable.runMayThrow(StorageProxy.java:1055)
at org.apache.cassandra.service.StorageProxy$DroppableRunnable.run(StorageProxy.java:1547)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)

为什么会这样？我正在用单种子检查我的本地？

更新 1：

我的日期表结构

CREATE TABLE date (
  key text PRIMARY KEY,
  date text,
  date_id text,
  day bigint,
  day_name text
) WITH COMPACT STORAGE AND
  bloom_filter_fp_chance=0.010000 AND
  caching='KEYS_ONLY' AND
  comment='' AND
  dclocal_read_repair_chance=0.000000 AND
  gc_grace_seconds=864000 AND
  read_repair_chance=0.100000 AND
  replicate_on_write='true' AND
  populate_io_cache_on_flush='false' AND
  compaction={'min_sstable_size': '52428800', 'class': 'SizeTieredCompactionStrategy'} AND
  compression={'chunk_length_kb': '64', 'sstable_compression': 'SnappyCompressor'};

我检查了 cassandra 日志，它的显示

ERROR [ReadStage:94] 2013-12-03 22:07:17,116 CassandraDaemon.java (line 192) Exception in thread Thread[ReadStage:94,5,main]
java.lang.AssertionError: DecoratedKey(-8665312888645846270,.......................<!--some bytes of numbers------->
/var/lib/cassandra/data/keyspace/columnfamily/keyspace-columnfamily-ic-1-Data.db
        at org.apache.cassandra.db.columniterator.SSTableNamesIterator.read(SSTableNamesIterator.java:119)
        at org.apache.cassandra.db.columniterator.SSTableNamesIterator.<init>(SSTableNamesIterator.java:60)
        at org.apache.cassandra.db.filter.NamesQueryFilter.getSSTableColumnIterator(NamesQueryFilter.java:81)
        at org.apache.cassandra.db.filter.QueryFilter.getSSTableColumnIterator(QueryFilter.java:68)
        at org.apache.cassandra.db.CollationController.collectTimeOrderedData(CollationController.java:132)
        at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:65)
        at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:1390)
        at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1213)
        at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1125)
        at org.apache.cassandra.db.Table.getRow(Table.java:347)
        at org.apache.cassandra.db.SliceByNamesReadCommand.getRow(SliceByNamesReadCommand.java:64)
        at org.apache.cassandra.service.StorageProxy$LocalReadRunnable.runMayThrow(StorageProxy.java:1033)
        at org.apache.cassandra.service.StorageProxy$DroppableRunnable.run(StorageProxy.java:1547)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:724)

目前我正在使用 cassandra-1.2.6。我用这个链接检查，这是 cassandra 问题吗？ https://issues.apache.org/jira/browse/CASSANDRA-4687

【问题讨论】：

您可以添加查询吗？（是不是很贵？）
嗨@lorcan，我用查询编辑了问题，请检查并提出您的建议
嗨@kumar，是的，看起来是同一个问题。可能最好在那里跟进？
我的回答仍然有效 - 如果您在 date 列中索引许多唯一值并查询您应该考虑重新建模。

标签： cassandra

【解决方案1】：

如果您的查询开销很大，这可能会导致 rpc 超时。对于不同类型的查询，沿着这条线有一堆 SO 问题，例如，Fetching all the records for a partitionID in cassandra gives RPC timeout、RPC timeout in cqlsh - Cassandra（选择计数（*）查询）。但是，您的问题专门与二级索引有关。

应避免查询二级索引如果唯一索引条目的数量很高，因为它们比按键查询贵得多（我怀疑如果您使用日期，情况就是这种情况） .也许有更好的数据建模方法？（如果您将数据模型添加到您的问题中，我可以尝试详细说明此答案。）

【讨论】：