MySQL Bugs: #74208: InnoDB: unable to purge a record

Bug #74208	InnoDB: unable to purge a record
Submitted:	3 Oct 2014 8:31	Modified:	6 Oct 2014 22:05
Reporter:	Sam Teale	Email Updates:
Status:	Duplicate	Impact on me:	None
Category:	MySQL Server: InnoDB storage engine	Severity:	S3 (Non-critical)
Version:	5.6.20-68	OS:	Linux (Ubuntu 12.04)
Assigned to:		CPU Architecture:	Any
Tags:	innodb, purge

Description:
Occasionally since upgrading from mysql 5.5 to 5.6 I am seeing the following errors on my mysql servers...

2014-10-01 10:14:42 7ff5ec951700  InnoDB: unable to purge a record

InnoDB: tuple DATA TUPLE: 2 fields;
  0: len 8; hex 000180000568e827; asc      h ';;
  1: len 8; hex 0001800008f2d2d7; asc         ;;

InnoDB: record PHYSICAL RECORD: n_fields 2; compact format; info bits 0
  0: len 8; hex 000180000568e827; asc      h ';;
  1: len 8; hex 0001800008f2d2d7; asc         ;;

space 97 offset 266225 (732 records, index id 230)
InnoDB: Submit a detailed bug report to http://bugs.mysql.com

To combat this I have run alter table on the databases to rebuild the tables but the error still keeps coming back every few days

This only effects one table with the same table schema (below) with different data sets on different servers.

Can you confirm the seriousness of these errors that appear multiple times, also what information would you like provided to work towards a resolution of this problem?

Thanks.

table_schema:

Create Table: CREATE TABLE `object_ancestors` (
  `object_id` bigint(20) unsigned NOT NULL,
  `ancestor_id` bigint(20) unsigned NOT NULL,
  `hops` int(10) unsigned NOT NULL,
  PRIMARY KEY (`object_id`,`ancestor_id`),
  KEY `ancestor_id` (`ancestor_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

How to repeat:
N/A

We also encountered this problem frequently on production environment.  Can anyone from official  verify  the severity of this bug ?

Duplicate of bug: http://bugs.mysql.com/bug.php?id=71720.