Qifan Chen has submitted this change and it was merged. ( http://gerrit.cloudera.org:8080/19233 )
Change subject: IMPALA-11720: Deflake FileMetadataLoaderTest due to FileSystem closed ...................................................................... IMPALA-11720: Deflake FileMetadataLoaderTest due to FileSystem closed IMPALA-11699 recently reverted the changes in FileMetadataLoaderTest that it no longer extends to FrontendTestBase. This causes tests in FileMetadataLoaderTest to become flaky if run individually. This is a subtle bug in FileMetadataLoader#load(), where we first call FileSystem#getFileSystem() to get a FileSystem object, and then call methods of FileSystemUtil which will trigger class loading of it and running its static code. FileSystem#getFileSystem() will create a FileSystem object in the first get and cache it for follow-up usage. Without extending FrontendTestBase, BackendConfig.INSTANCE is not initialized when the test is run. So the static code in FileSystemUtil lazily initializes BackendConfig.INSTANCE, which initializes FeSupport and finally calls JniUtil::InitLibhdfs(). In this method, a FileSystem object is get and closed. This is exactly the FileSystem object created in FileMetadataLoader#load(). So the following usage on it causes an IOException of "Filesystem closed". The purpose of JniUtil::InitLibhdfs() is to make a simple call on libhdfs to make it initialize the JVM. This is crucial when launching from C++ codes for impalad and catalogd to init the embedded JVM. So we should keep it unchanged. The fix for this bug is to maintain the state of BackendConfig.INSTANCE in the static code of FileSystemUtil (i.e., keep un-initialized or initialized), which avoids the subtle side effects. Tests: - Verified tests in FileMetadataLoaderTest individually Change-Id: Ib6f96950210c9a0124fe03696ef334cb00b057ab Reviewed-on: http://gerrit.cloudera.org:8080/19233 Tested-by: Impala Public Jenkins <[email protected]> Reviewed-by: Michael Smith <[email protected]> Reviewed-by: Qifan Chen <[email protected]> --- M fe/src/main/java/org/apache/impala/common/FileSystemUtil.java M fe/src/test/java/org/apache/impala/common/FileSystemUtilTest.java 2 files changed, 21 insertions(+), 14 deletions(-) Approvals: Impala Public Jenkins: Verified Michael Smith: Looks good to me, but someone else must approve Qifan Chen: Looks good to me, approved -- To view, visit http://gerrit.cloudera.org:8080/19233 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: merged Gerrit-Change-Id: Ib6f96950210c9a0124fe03696ef334cb00b057ab Gerrit-Change-Number: 19233 Gerrit-PatchSet: 4 Gerrit-Owner: Quanlong Huang <[email protected]> Gerrit-Reviewer: Daniel Becker <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Michael Smith <[email protected]> Gerrit-Reviewer: Qifan Chen <[email protected]> Gerrit-Reviewer: Quanlong Huang <[email protected]>
