无法启动titan-server（Titan与Cassandra和Rexster）

Question

我正在尝试为我的某个应用程序在cassandra 上实现 titan graph数据库。根据文档，我已经下载并解压缩了titan-cassandra-0.3.2，当它尝试以titan.sh和titan-server-rexster.xml作为参数运行titan-server-cassandra.properties时，我面临以下错误：

在下面的堆栈跟踪中，它显示"Cannot locate /opt/isv/app/pkgs/titan-cassandra-0.3.2/config/cassandra.yaml"，但我确实在该位置有该文件。 有人可以帮忙吗？

WARN  org.apache.cassandra.utils.CLibrary  - Unable to lock JVM memory (ENOMEM). This can result in part of the JVM being swapped out, especially with mmapped I/O enabled. Increase RLIMIT_MEMLOCK or run Cassandra as root.
72   [pool-1-thread-1] ERROR org.apache.cassandra.config.DatabaseDescriptor  - Fatal configuration error
org.apache.cassandra.exceptions.ConfigurationException: Cannot locate /opt/isv/app/pkgs/titan-cassandra-0.3.2/config/cassandra.yaml
        at org.apache.cassandra.config.DatabaseDescriptor.getStorageConfigURL(DatabaseDescriptor.java:113)
        at org.apache.cassandra.config.DatabaseDescriptor.loadYaml(DatabaseDescriptor.java:130)
        at org.apache.cassandra.config.DatabaseDescriptor.<clinit>(DatabaseDescriptor.java:122)
        at org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:150)
        at org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:366)
        at org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:409)
        at com.thinkaurelius.titan.diskstorage.cassandra.embedded.CassandraDaemonWrapper$CassandraStarter.run(CassandraDaemonWrapper.java:64)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
        at java.util.concurrent.FutureTask.run(FutureTask.java:138)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
        at java.lang.Thread.run(Thread.java:619)
Cannot locate /opt/isv/app/pkgs/titan-cassandra-0.3.2/config/cassandra.yaml
Fatal configuration error; unable to start server.  See log for stacktrace.

Answer 1

ENOMEM的完整演练在这里

http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/troubleshooting/trblshootInsufficientResources_r.html也不要忘记

基本上编辑附加以下内容的/etc/security/limits.conf文件

memlock unlimited
nofile 100000
nproc 32768
as unlimited

然后运行sysctl -p