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Vinayakumar B commented on HADOOP-17306: ---------------------------------------- Hi [~Jim_Brennan], Thanks for pointing to test failures. AFAIK, test failures are due to setting timestamp of {{LocalResource}} with value returned by {{File.lastModified()}} all in test code explicitly for the scriptfile used for tests. As mentioned in this Jira title, {{File.lastModified()}} is broken and looses accuracy. I tried replacing {{File.lastModified()}} calls with {{Files.getLastModifiedTime(file.toPath()).toMillis()}}, all tests passed. AM's sets the timestamp using the value returned by {{FileStatus#getModifiedTime()}} in which case, it will be consistent. So I dont think any problem with the production code as long as {{FileStatus#getModificationTime()}} is used. As Steve mentioned, relying on modificationTime and length may not be a good idea to detect changes. There could be possibilities of corruption > RawLocalFileSystem's lastModifiedTime() looses milli seconds in JDK < 10.b09 > ---------------------------------------------------------------------------- > > Key: HADOOP-17306 > URL: https://issues.apache.org/jira/browse/HADOOP-17306 > Project: Hadoop Common > Issue Type: Bug > Components: fs > Reporter: Vinayakumar B > Assignee: Vinayakumar B > Priority: Major > Labels: pull-request-available > Time Spent: 1h 40m > Remaining Estimate: 0h > > RawLocalFileSystem's FileStatus uses {{File.lastModified()}} api from JDK. > This api looses milliseconds due to JDK bug. > [https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8177809] > This bug fixed in JDK 10 b09 onwards and still exists in JDK 8 which is still > being used in many productions. > Apparently, {{Files.getLastModifiedTime()}} from java's nio package returns > correct time. > Use {{Files.getLastModifiedTime()}} instead of {{File.lastModified}} as > workaround. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org