Pawel Szlendak created CASSANDRA-13835: ------------------------------------------
Summary: Thrift get_slice responds slower on Cassandra 3 Key: CASSANDRA-13835 URL: https://issues.apache.org/jira/browse/CASSANDRA-13835 Project: Cassandra Issue Type: Bug Reporter: Pawel Szlendak Attachments: attack.py, cassandra120_get_slice_reply_time.png, cassandra310_get_slice_reply_time.png I have recently upgraded from Cassandra 1.2.18 to Cassandra 3.10 and was surprised to notice performance degradation of my server application. I dug down through my application stack only to find out that the cause of the performance issue was slower response time of Cassandra 3.10 get_slice as compared to Cassandra 1.2.18 (almost x3 times slower on average). I am attaching a python script (attack.py) here that can be used to reproduce this issue on a Windows platform. The script uses the pycassa python library that can easily be installed using pip. REPRODUCTION STEPS: 1. Install Cassandra 1.2.18 from https://archive.apache.org/dist/cassandra/1.2.18/apache-cassandra-1.2.18-bin.tar.gz 2. Run Cassandra 1.2.18 from cmd console using cassandra.bat 3. Create a test keyspace and an empty CF using attack.py script python attack.py create 4. Run some get_slice queries to an empty CF and note down the average response time python attack.py get_slice count: 788 get_slice total response time: 0.31299996376 get_slice average response time: 0.000397208075838 5. Stop Cassandra 1.2.18 and install Cassandra 3.10 from https://archive.apache.org/dist/cassandra/3.10/apache-cassandra-3.10-bin.tar.gz 6. Tweak cassandra.yaml to run thrift service (start_rpc=true) and run Cassandra from an elevated cmd console using cassandra.bat 7. Create a test keyspace and an empty CF using attack.py script python attack.py create 8. Run some get_slice queries to an empty CF using attack.py and note down the average response time python attack.py get_slice count: 788 get_slice total response time: 1.16499996185 get_slice average response time: 0.00147842634753 9. Compare the average response times EXPECTED: get_slice response time of Cassandra 3.10 is not worse than on Cassandra 1.2.18 ACTUAL: get_slice response time of Cassandra 3.10 is x3 worse than that of Cassandra 1.2.18 REMARKS: - this seems to happen only on Windows platform (tested on Windows 10 and Windows Server 2008 R2) - running the very same procedure on Linux (Ubuntu) renders roughly the same response times - I sniffed the traffic to/from Cassandra 1.2.18 and Cassandra 3.10 and it can been seen that Cassandra 3.10 responds slower (Wireshark dumps attached) - when attacking the server with concurrent get_slice queries I can see lower CPU usage for Cassandra 3.10 that for Cassandra 1.2.18 I am willing to work on this on my own if you guys give me some tips on where to look for. I am also aware that this might be more Windows/Java related, nevertheless, any help from your side would be much appreciated. -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org