HTraceConfiguration Class Not Found Exception

I want to run YCSB with Cassandra, “ycsb load” command failed immediately with the following error:

bin/ycsb.sh load cassandra-cql -p hosts="10.40.1.167" -P workloads/workloada
/usr/lib/jvm/jre-1.8.0-openjdk/bin/java  -classpath /home/cc/YCSB/conf:/home/cc/YCSB/core/target/core-0.12.0-SNAPSHOT.jar:/home/cc/YCSB/cassandra/target/cassandra-binding-0.12.0-SNAPSHOT.jar:/home/cc/YCSB/cassandra/target/dependency/cassandra-driver-core-3.0.0.jar:/home/cc/YCSB/cassandra/target/dependency/guava-16.0.1.jar:/home/cc/YCSB/cassandra/target/dependency/metrics-core-3.1.2.jar:/home/cc/YCSB/cassandra/target/dependency/netty-buffer-4.0.33.Final.jar:/home/cc/YCSB/cassandra/target/dependency/netty-codec-4.0.33.Final.jar:/home/cc/YCSB/cassandra/target/dependency/netty-common-4.0.33.Final.jar:/home/cc/YCSB/cassandra/target/dependency/netty-handler-4.0.33.Final.jar:/home/cc/YCSB/cassandra/target/dependency/netty-transport-4.0.33.Final.jar:/home/cc/YCSB/cassandra/target/dependency/slf4j-api-1.6.4.jar com.yahoo.ycsb.Client -load -db com.yahoo.ycsb.db.CassandraCQLClient -p hosts=10.40.1.167 -P workloads/workloada
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/htrace/core/HTraceConfiguration
        at com.yahoo.ycsb.Client.main(Client.java:947)
Caused by: java.lang.ClassNotFoundException: org.apache.htrace.core.HTraceConfiguration
        at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        ... 1 more

I did not install htrace on my computer. In the latest version of YCSB, is htrace turned on by default? If so, is there a way to turn it off?

Also, I am curious how ‘deeply’ is htrace integrated with YCSB, only at the ‘global’ YCSB client level? Or is the htrase code implemented in every individual database interfaces?

[busbey]

In a new issue, sure. Go to “issues” for the project and then click on “new issue”.

[busbey]

This looks like an error in the classpath generation for maven source runs. Can you try one of more of the following:

• run from the 0.11.0 release’s binary artifact
• build a binary artifact from a git checkout and run from that artifact
• run from source checkout using the old ‘ycsb’ python script rather than the newer bash

I did not install htrace on my computer. In the latest version of YCSB, is htrace turned on by default? If so, is there a way to turn it off?

By default HTrace is set to no tracing. However, like log levels in e.g. slf4j this still requires a call into the htrace library (to check if tracing is on, for example).

Also, I am curious how ‘deeply’ is htrace integrated with YCSB, only at the ‘global’ YCSB client level? Or is the htrase code implemented in every individual database interfaces?

AFAIK it’s currently implemented around the wrapper we layer on top of the storage interfaces. That means we trace each kind of operation we do in YCSB. However, tracing through the individual storage engines would depend on if the client libraries of a given storage system.