| Bug #87282 | WL#9499 can cause extra warnings on every crashing testcase | ||
|---|---|---|---|
| Submitted: | 2 Aug 2017 10:40 | Modified: | 4 Oct 2017 8:52 |
| Reporter: | Laurynas Biveinis | Email Updates: | |
| Status: | Verified | Impact on me: | |
| Category: | Tests: Server | Severity: | S3 (Non-critical) |
| Version: | 8.0.2 | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
| Tags: | crash recovery, innodb, mtr | ||
[5 Aug 2017 7:31]
Laurynas Biveinis
Bug 87282 fix for 8.0.2 (*) I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.
Contribution: bug87282-8.0.2.patch (application/octet-stream, text), 3.47 KiB.
[5 Aug 2017 7:32]
Laurynas Biveinis
I hope I got the suppression regexp right; all I know is that with the patch, the only occurrences of this error were on the testcases with missing not_crashrep.inc so far (the patch adds a few)
[7 Aug 2017 4:40]
Erlend Dahl
This is a known issue in internal testing.
[7 Aug 2017 4:46]
Erlend Dahl
Discussed with Sunny Bains (developer), the code producing the warning is slated for removal in an upcoming WL.
[4 Oct 2017 8:52]
Laurynas Biveinis
The warning has been removed by WL#9535/WL#9536 in 8.0.3 [1], this bug has been fixed. [1]: commit 34526482834a8c3deb05bdf831321d93ce225ccd Author: Jimmy Yang <jimmy.yang@oracle.com> Date: Thu Aug 17 00:34:24 2017 +0200 InnoDB NewDD worklogs(WL#9535 and WL#9536) to support Atomic DDL and completely remove old InnoDB system tables: 1. WL#9535: InnoDB_New_DD: Remove InnoDB System Table and modify the view of their I_S counterparts This worklog obsoletes all InnoDB System tables, which are no longer used and could only be accessed by upgrade. All metadata is now persisted and read from DD system tables in "mysql tablespace" instead of "old" InnoDB System Tables. All corresponding information_schema.innodb_sys_* tables are replaced by new internal system views. These new views have the name similar to the names of old system tables, just removing the 'SYS_' from the middle of the names. 2. WL#9536: InnoDB_New_DD: Support crash-safe DDL This worklog starts to support crash-safe DDL for InnoDB. DDLs like CREATE TABLE, DROP TABLE, RENAME TABLE, TRUNCATE TABLE, ALTER TABLE, CREATE TABLESPACE and DROP TABLESPACE are covered by this worklog. DDLs operations including DD system table updates and corresponding file changes(create, delete, rename etc.) are atomic. Physical data files would be synchronized with the transaction for DDL, thus there should be no physical data files for temporary tables or FTS auxiliary tables, etc. left after recovery.
Description: On 8.0.2, some testcases randomly and very intermittently fail their warning checks, e.g. binlog_gtid.binlog_gtid_exhausted 'stmt' w1 [ fail ] Found warnings/errors in server log file! Test ended at 2017-08-01 06:36:09 line 2017-08-01T06:36:06.805163Z 1 [Warning] InnoDB: File '/mnt/workspace/mysql-5.7-param/BUILD_TYPE/debug/Host/debian-jessie-64bit/build/mysql-test/var/1/mysqld.1/data/tablespaces.open.1' size is 0 bytes. Must be at least 12 bytes .... repeated 1 times: [Warning] InnoDB: File '/mnt/workspace/mysql-5.7-param/BUILD_TYPE/debug/Host/debian-jessie-64bit/build/mysql-test/var/1/mysqld.1/data/tablespaces.open.1' size is 0 bytes. Must be at least 12 bytes ^ Found warnings in /mnt/workspace/mysql-5.7-param/BUILD_TYPE/debug/Host/debian-jessie-64bit/build/mysql-test/var/1/log/mysqld.1.err ok The only common thing between the randomly failing testcases seems to be that they are all crashing ones, and tend to be in rpl suites. How to repeat: Not sure. Host being slow seems to raise the occurrence rate. Testcase being a replication one might help with host being slow Suggested fix: An IMHO plausible explanation is InnoDB master thread making checkpoints in the background. Each log checkpoint with WL#9499 now calls fil_tablespace_open_sync_to_disk, which calls fil_system->m_open.to_file(), which writes the tablespace maps for crash recovery. The write is done in steps, and one of the steps is truncating the file to zero. If another thread hits the testcase crash between the truncate and the tablespace map write/flush, the crash recovery will hit this warning, intended or not. This is a bit hard to confirm as it needs saving the server stacktraces at the crash injection time. If the above is correct, then it should be fixed by suppressing the warning. Adding a suppression to the global MTR list does not look correct as it would cover non-crashing testcases too. Perhaps include/not_crashrep.inc could be repurposed to hold this mtr.add_suppression call.