IMPALA-3819: Clarify stale block metadata warning message We got user reports that the warning we display for stale block metadata is confusing and gives an impression that it can cause incorrect results. This commit clarifies the warning message.
Change-Id: Ie9eb2672393c5ff4e0670d247d684278283012a3 Reviewed-on: http://gerrit.cloudera.org:8080/11433 Reviewed-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Tested-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Project: http://git-wip-us.apache.org/repos/asf/impala/repo Commit: http://git-wip-us.apache.org/repos/asf/impala/commit/5129cf94 Tree: http://git-wip-us.apache.org/repos/asf/impala/tree/5129cf94 Diff: http://git-wip-us.apache.org/repos/asf/impala/diff/5129cf94 Branch: refs/heads/master Commit: 5129cf94cf90ff84d83e1fb2a477c8d22fbe4eb8 Parents: a0a4044 Author: Bharath Vissapragada <bhara...@cloudera.com> Authored: Wed Sep 12 12:56:33 2018 -0700 Committer: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Committed: Thu Sep 13 20:30:59 2018 +0000 ---------------------------------------------------------------------- be/src/exec/hdfs-scan-node-base.cc | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/impala/blob/5129cf94/be/src/exec/hdfs-scan-node-base.cc ---------------------------------------------------------------------- diff --git a/be/src/exec/hdfs-scan-node-base.cc b/be/src/exec/hdfs-scan-node-base.cc index 09c2c0d..b11dcdc 100644 --- a/be/src/exec/hdfs-scan-node-base.cc +++ b/be/src/exec/hdfs-scan-node-base.cc @@ -911,9 +911,11 @@ void HdfsScanNodeBase::StopAndFinalizeCounters() { if (unexpected_remote_bytes_->value() >= UNEXPECTED_REMOTE_BYTES_WARN_THRESHOLD) { runtime_state_->LogError(ErrorMsg(TErrorCode::GENERAL, Substitute( - "Read $0 of data across network that was expected to be local. " - "Block locality metadata for table '$1.$2' may be stale. Consider running " - "\"INVALIDATE METADATA `$1`.`$2`\".", + "Read $0 of data across network that was expected to be local. Block locality " + "metadata for table '$1.$2' may be stale. This only affects query performance " + "and not result correctness. One of the common causes for this warning is HDFS " + "rebalancer moving some of the file's blocks. If the issue persists, consider " + "running \"INVALIDATE METADATA `$1`.`$2`\".", PrettyPrinter::Print(unexpected_remote_bytes_->value(), TUnit::BYTES), hdfs_table_->database(), hdfs_table_->name()))); }
