Datastax Cassandra Administrator Certification Questions and Answer (Pratice Questions and Dumps)

Question-: Which of the following detail can be found using the “cassandra-stress� test with regards to the Java garbage collection?
A. Number of garbage collection
B. Longest garbage collection in milliseconds
C. Total garbage collection in milliseconds
D. Size of the garbage collection in milliseconds

Answer: A, B, C,D

Explanation: “Cassandra-stress� tool is also good to find the garbage collection detail for the Data model you have designed. And with this tool you would get to know all the listed option after running the stress testing.
A. Number of garbage collection
B. Longest garbage collection in milliseconds
C. Total garbage collection in milliseconds
D. Size of the garbage collection in milliseconds


Admin only



Question-: Which of the following information would be printed when you run the nodetool gcstats subcommand?
A. Cluster wide garbage collection info
B. Node specific JVM gc collection detail.
C. Amount of the time spent for entire cluster for garbage collection
D. Total number of gc session across the cluster.
E. Total time spent for the garbage collection by individual node.


Answer: B,E

Explanation: Remember that nodetool utility is mainly for individual node and most of the information you would get it is not for entire cluster but rather for individual node. And by running the gcstats command you can get the following detail.
- Node specific info for the JVM garbage collection
- Measurements which accumulates since previous invocation of gcstats.
- And report include the following detail
a. Length of time taken for the garbage collection.
b. Total amount of memory released by doing the gc on that node
c. Total number of gc session

Admin only


Question-: If you see the split brain situation for a particular node in the Cassandra cluster, you can utilize the “nodetool gossipinfo� command, for further analysis?
A. True
B. False

Answer: A
Exp: Yes, using gossipinfo subcommand you can get a more detail about the gossip detail for the particular node and can check whether they are having the same SCHEMA entry or not. Which would be helpful for finding the “split-brain� situation for the node.

Admin only

Related Questions

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Question-: When garbage collection removes the objects or reclaim memory. From where the memory would be reclaimed?
A. Stack
B. Heap
C. Hard Disk
D. CPU Cache


Question-: If you wanted to have less number of GC pauses then you should set� MAX_HEAP_SIZE� with large value?
A. True
B. False


Question-: Which of the following option would help in communicating with the application at runtime?
A. Garbage collection
B. JMX
C. Gossip protocol



Question-: Which of the following is true with regards to the Java garbage collection?
A. Garbage collection is responsible for cleaning the heap memory area in Java for the objects which are not being used or referred.
B. If you have a bigger size of heap memory area then garbage collection would take more time to clean out the object if that area is filled.
C. Number of CPU can also affect the performance
D. There is only one algorithm on which garbage collection work which is G1


Question-: To run the Cassandra database smoothly, you wanted to have minimum number of GC pauses as well as frequency of garbage collection?
A. True
B. False


Question-: Wrong data model design can lead to heavy garbage collection?
A. True
B. False