steveloughran commented on pull request #3341: URL: https://github.com/apache/hadoop/pull/3341#issuecomment-909207833
> they are the same across different tests/test classes run in parallel > we do reset currently during test run but it hasn't helped, so marking in pom for sequential seems to be the only resort I think you are a bit confused about what parallel/sequential means. I stated this [a few days ago](https://github.com/apache/hadoop/pull/3341#discussion_r696867103); nothing has changed in Maven since then. 1. In the parallel test run phase, Maven surefire/failsafe spawns multiple processes to execute test suite in parallel. 2. Within a process, tests are run sequentially. The issue is not parallel execution, the issue is state persisting from previous runs. The reason things work in sequential & not parallel is the `<reuseForks>false</reuseForks>` flag. That's all. it has nothing to do with parallel test runs -not directly. Indirectly it could be due to something like: the fact tests take longer to run, or that the destination store is updated by other processes. Before moving into sequential phase, and so making test runs slower, can we work out why the `statistics.reset();` calls aren't working. As I keep saying: it is not failing from parallel tests running. Meaning it could be one of * stats references not binding properly * counters double/under-counting in some circumstances. * state of remote store affecting results. * something remaining active in the process * reset() not working. I think we need to understand more before committing this -otherwise it's not so much a fix for the problem as a "we changed this and it went away" kind of PR. It probably is just some state left over from the previous test run -but there is a risk of it being something real. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
