[ https://issues.apache.org/jira/browse/CASSANDRA-11053?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Stefania updated CASSANDRA-11053: --------------------------------- Attachment: bisect_test.py > COPY FROM on large datasets: fix progress report and debug performance > ---------------------------------------------------------------------- > > Key: CASSANDRA-11053 > URL: https://issues.apache.org/jira/browse/CASSANDRA-11053 > Project: Cassandra > Issue Type: Bug > Components: Tools > Reporter: Stefania > Assignee: Stefania > Labels: doc-impacting > Fix For: 2.1.14, 2.2.6, 3.0.5, 3.5 > > Attachments: bisect_test.py, copy_from_large_benchmark.txt, > copy_from_large_benchmark_2.txt, parent_profile.txt, parent_profile_2.txt, > worker_profiles.txt, worker_profiles_2.txt > > > h5. Description > Running COPY from on a large dataset (20G divided in 20M records) revealed > two issues: > * The progress report is incorrect, it is very slow until almost the end of > the test at which point it catches up extremely quickly. > * The performance in rows per second is similar to running smaller tests with > a smaller cluster locally (approx 35,000 rows per second). As a comparison, > cassandra-stress manages 50,000 rows per second under the same set-up, > therefore resulting 1.5 times faster. > See attached file _copy_from_large_benchmark.txt_ for the benchmark details. > h5. Doc-impacting changes to COPY FROM options > * A new option was added: PREPAREDSTATEMENTS - it indicates if prepared > statements should be used; it defaults to true. > * The default value of CHUNKSIZE changed from 1000 to 5000. > * The default value of MINBATCHSIZE changed from 2 to 10. -- This message was sent by Atlassian JIRA (v6.3.4#6332)