Here at Percona, we operate on the premise that full transparency makes a product better. We strive to build the best open-source database products, but also to help you manage any issues that arise in any of the databases that we support. And, in true open source form, report back on any issues or bugs you might encounter along the way.
We constantly update our bug reports and monitor other boards to ensure we have the latest information, but we wanted to make it a little easier for you to keep track of the most critical ones. These posts are a central place to get information on the most noteworthy open and recently resolved bugs.
In this November 2021 edition of our monthly bug report, we have the following list of bugs:
Percona Server for MySQL/MySQL Bugs
PS-7919: Percona Server crashes during CREATE TABLE statements. The problem was seen when tables have many partitions and there were already many tablespaces present in the instance.
Affects Version/s: 8.0 [Tested/Reported version 8.0.25]
Fixed Version/s: 8.0.26
PS-7866 (MySQL#104961): MySQL crashes when running a complex query with JOINS. In MySQL error log it only adds a single line as “Segmentation fault (core dumped)” and there are no further details like backtraces in MySQL error log. Further analyzing the core dump shows that something happened at CreateIteratorFromAccessPath.
Affects Version/s: 8.0 [Tested/Reported version 8.0.23, 8.0.25]
PS-1653/PS-4935 (MySQL#78612, MySQL#97001 ): Optimizer Issue for query with ORDER BY+ LIMIT. In some cases, Optimizer chooses a full table scan instead of an index range scan on query order by primary key with limit.
- It happens only when we use ORDER BY and LIMIT together.
- Issue reproducible for a table with and without primary key.
Affects Version/s: 5.7,8.0 [Tested/Reported version 5.7.27]
Fixed Version/s: 8.0.21, 5.7.33
Recently MySQL 8.0.27 was released with some major changes/ Improvements, Following are the few noticeable changes:
- Previously, MySQL user accounts were authenticated to the server using a single authentication method. MySQL now supports multifactor authentication (MFA), which makes it possible to create accounts that have up to three authentication methods.
- Changes for CREATE USER and ALTER USER syntax have been extended to use MFA.
- authentication_policy system variable enables MFA policy.
- Client programs have new –password1, –password2, and –password3 command-line options for specifying multiple passwords. For applications that use the C API, the new MYSQL_OPT_USER_PASSWORD option for the mysql_options4() C API function enables the same capability.
- The default_authentication_plugin variable is deprecated as of MySQL 8.0.27, New replacement variable authentication_policy system variable, which is introduced in MySQL 8.0.27 with the multifactor authentication feature.
- MySQL MTS Replication: Multithreading is now enabled by default for replica servers.
Defaults values for MTS variables as follows,
replica_preserve_commit_order=1.
replica_parallel_type=LOGICAL_CLOCK
Percona XtraDB Cluster
PXC-3724: PXC node crashes with long semaphore. This issue occurred due to locking when writing on multiple nodes in PXC cluster. This is critical as it blocks all nodes to perform any transactions and finally crashes PXC node.
Affects Version/s: 8.0 [Tested/Reported version 8.0.22,8.0.25]
PXC-3729: PXC node fails with two applier threads due to conflict. In a certain combination of a table having both primary key and (multi-column) unique key, and highly concurrent write workload updating similar UK values, parallel appliers on secondary nodes may conflict with each other, causing node aborts with inconsistency state. These can be seen even when writes are going to a single writer node only. As transactions were already certified and replicated, they should never fail on the appliers.
Affects Version/s: 8.0 [Tested/Reported version 8.0.21]
Fixed Version/s: 8.0.25
PXC-3449: When ALTER TABLE (TOI) is executed in the user session, sometimes it happens that it conflicts (MDL) with high priority transaction, which causes BF-BF abort and server termination.
Affects Version/s: 8.0 [Tested/Reported version 8.0.21]
Fixed Version/s: 8.0.25
PXC-3387: Server hits the assertion while the query performs an intermediate commit during update of table stats in the Data Dictionary. You will see this issue when autocommit=0
Affects Version/s: 8.0 [Tested/Reported version 8.0.21]
Fixed Version/s: 8.0.25
Percona XtraBackup
PXB-2629: Downloading backup using xbcloud on Debian-10 not working. Download stuck at some point for forever or it fails with the Segmentation fault message at the end.
Found issue with curl version for this issue. The default curl version on Debian-10 is curl 7.64.0 libcurl/7.64.0 upgrading it to curl 7.74.0 (x86_64-pc-linux-gnu) libcurl/7.74.0 version fix the issue.
Affects Version/s: 8.0 [Tested/Reported version 8.0.21]
Fixed Version/s: 8.0.25
Percona Toolkit
PT-1889: Incorrect output when using pt-show-grants for users based on MySQL roles. As a result, they can not be applied back properly on the MySQL server. Due to this, we can not use pt-show-grants for MySQL roles until this issue is fixed.
Affects Version/s: 3.2.1
PT-1747: pt-online-schema-change was bringing the database into a broken state when applying the “rebuild_constraints” foreign keys modification method if any of the child tables were blocked by the metadata lock.
Affects Version/s: 3.0.13
Fixed Version: 3.4.0
PMM [Percona Monitoring and Management]
PMM-7116: MongoDB ReplSet Summary Dashboard shows incorrect replset member’s state: STARTUP instead of PRIMARY.
Affects Version/s: 2.x [Tested/Reported version 2.12,2.20]
Fixed Version: 2.25.0
PMM-9085: Upgrading to 2.22 pmm-managed component crashes with the following error: panic: interface conversion: agentpb.AgentResponsePayload is nil, not *agentpb.GetVersionsResponse
Affects Version/s: 2.x [Tested/Reported version 2.22]
Fixed Version: 2.25.0
PMM-9156: pmm-agent paths-base option not working for pmm2-client binary installation in PMM 2.23.0. Starting pmm-agent process gives “level=error msg=”Error reading textfile collector directory”
Affects Version/s: 2.x [Tested/Reported version 2.23]
PMM-7846: Adding MongoDB instance via pmm-admin with tls option not working and failing with error Connection check failed: timeout (context deadline exceeded).
Affects Version/s: 2.x [Tested/Reported version 2.13, 2.16]
Percona Server for MongoDB
PSMDB-892: RWC defaults pollute the logs with duplicate “Refreshed RWC defaults” messages as a result log is saturated with the message in the title.
Affects Version/s: 4.4.6
Fixed Version: 4.4.8
WT-7984: This issue in MongoDB 4.4.8 causes a checkpoint thread to read and persist an incomplete version of data to disk. Data in memory remains correct unless the server crashes or experiences an unclean shutdown. Then, the inconsistent checkpoint is used for recovery and introduces corruption.
The bug is triggered on cache pages that receive an update during a running checkpoint and which are evicted during the checkpoint.
Affects Version/s: 4.4.8
Fixed Version: 4.4.9
PSMDB-671: createBackup returns ok:1 for archived backup even when there is no disk space available.
Affects Version/s: 4.0.12-6, 4.2.1-1, 3.6.15-3.5
Fixed Version:3.6.19-7.0, 4.0.20-13, 4.2.9-9
Percona Distribution for PostgreSQL
DISTPG-317: Installing Percona-PostgreSQL13 from its repository, the package dependencies are such it is going to remove PostgreSQL Community 12 installed.
Affects Version/s: 13.4
Summary
We welcome community input and feedback on all our products. If you find a bug or would like to suggest an improvement or a feature, learn how in our post, How to Report Bugs, Improvements, New Feature Requests for Percona Products.
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