wangsheng has posted comments on this change. ( http://gerrit.cloudera.org:8080/14319 )
Change subject: IMPALA-8984: Fix race condition in creating Kudu table ...................................................................... Patch Set 13: > (1 comment) This bug happened when submit several 'create if not exists' queries concurrently to create kudu managed table(these queries are same, at lease same table name, without Kudu-HMS Integration). If one query obtain 'metastoreDdlLock_', this means already create table in kudu storage(KuduCatalogOpExecutor.createManagedTable), then other query prepare to create table in kudu storage, but already exists, thus throw an exception , and this caused table droped in kudu storage which created by first query. And then the first query continue create table in hms which already obtain 'metastoreDdlLock_', and to the end. These queries all execute successful, but table only exist in hms, not in kudu storage. This bug is hard to reprodue due to relying on threads execute path, so I mock this situation in a test case: First create a kudu managed table, then deleted it from catalog, still reserved in metastore. Then submit the same ddl request again, and the original code would lead to table been deleted in kudu storage, and thus we would got an incompleted table when invalidated table. But with this patch fixed, we would got an normal kudu table. -- To view, visit http://gerrit.cloudera.org:8080/14319 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I1a4047bcdaa6b346765b96e8c36bb747a2b0091d Gerrit-Change-Number: 14319 Gerrit-PatchSet: 13 Gerrit-Owner: wangsheng <sky...@163.com> Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Gerrit-Reviewer: Quanlong Huang <huangquanl...@gmail.com> Gerrit-Reviewer: Tim Armstrong <tarmstr...@cloudera.com> Gerrit-Reviewer: Vihang Karajgaonkar <vih...@cloudera.com> Gerrit-Reviewer: wangsheng <sky...@163.com> Gerrit-Comment-Date: Thu, 12 Dec 2019 06:03:53 +0000 Gerrit-HasComments: No
