[ https://issues.apache.org/jira/browse/IMPALA-11961?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17743092#comment-17743092 ]
ASF subversion and git services commented on IMPALA-11961: ---------------------------------------------------------- Commit 14a5e9a20af59af7a03a9fb480c077d1d8a38187 in impala's branch refs/heads/master from Daniel Becker [ https://gitbox.apache.org/repos/asf?p=impala.git;h=14a5e9a20 ] IMPALA-12239: BitWidthZeroRepeated seems to be flaky RleTest.BitWidthZeroRepeated seems to be flaky in release builds. A possible error message is this: Value of: 0 Expected: val Which is: '\x9F' (159) Stacktrace .../Impala/be/src/util/rle-test.cc:410 Value of: 0 Expected: val Which is: '\x9F' (159) The problem seems to be around this 'memcpy()' call: https://github.com/apache/impala/blob/3e9408480c5285ca925576b7486b35593407a32a/be/src/util/bit-stream-utils.inline.h#L237. We're almost certainly running into undefined behaviour because - the error only occurs in release mode, not in debug mode (not even in ASAN or UBSAN mode) - if we add something around the 'memcpy()', for example printing 'buffer_pos_' or 'v', the error doesn't occur - the value with which the test fails, i.e. the value it reads instead of the expected 0 is non-deterministic. The failure occurs since https://gerrit.cloudera.org/#/c/20073/ (IMPALA-11961/IMPALA-12207: Add Redhat 9 / Ubuntu 22 support), which upgraded gperftools. We couldn't find the root cause of the bug but the most probable possibilities are the following: - there's a bug in Impala that leads to undefined behaviour and that manifests in the test failure with the new gperftools version but not with the old one - there's a bug in the new gperftools version (2.10). Downgrading gperftools is not an option because it is necessary for Redhat 9 and Ubuntu 22. There is a workaround that causes the test to pass - putting the 'memcpy()' in a conditional block: if (LIKELY(buffer_pos_ != buffer_end_)) { memcpy(v, buffer_pos_, num_bytes); buffer_pos_ += num_bytes; } else { ... } This most probably does not address the root cause, however; for more see the Jira ticket. Testing: - manually verified that the test RleTest.BitWidthZeroRepeated passes in a release build Change-Id: I84645271101b4bd594dd25929924a3549c223244 Reviewed-on: http://gerrit.cloudera.org:8080/20187 Reviewed-by: Joe McDonnell <joemcdonn...@cloudera.com> Tested-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com> > Add support for Ubuntu 22.04 > ---------------------------- > > Key: IMPALA-11961 > URL: https://issues.apache.org/jira/browse/IMPALA-11961 > Project: IMPALA > Issue Type: New Feature > Components: Infrastructure > Reporter: Quanlong Huang > Assignee: Joe McDonnell > Priority: Major > Fix For: Impala 4.3.0 > > > This tracks the support for Ubuntu 22.04. We should ensure the toolchain can > build on it first. -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org