Explore the powerful features of Aurora Serverless V2 for MySQL in this informative blog series. Learn about read-only scaling, parameter support, and cost performance. Compare costs between Provisioned Aurora and Aurora Serverless V2. Discover key takeaways for optimizing your MySQL deployment on the cloud. Read now!
[Read more]Discover how to troubleshoot a MySQL replica IO thread stuck in a connecting state. Learn about the replication architecture, security group rules for AWS EC2 instances, and how to address common issues like network restrictions and bind address configuration.
MySQL is a powerful database management and a widely used cloud database service. One of its key features is the ability to create replicas of a master database to improve its availability and scalability. However, at times the IO thread in a MySQL replica may get stuck in a connecting state, which can cause replication issues and affect the overall data consistency …
[Read more]The End-of-Life (EOL) date for MySQL 5.7 is scheduled for October 2023, which means that after that date, MySQL 5.7 will no longer receive updates, bug fixes, or security patches. This does not mean that MySQL 5.7 will stop working after the EOL date, but it does mean that any issues or vulnerabilities discovered after that date will not be addressed, This can leave your database at risk of security breaches or performance issues. AWS RDS support for MySQL will also hold good only till October 2023.
To avoid these potential issues, it is recommended to upgrade to a newer version of MySQL before the EOL date for MySQL 5.7. Upgrading to a newer version such as MySQL 8 …
[Read more]Recently, while doing a test process to examine resource usage and the time required to alter the table using pt-osc, it leads to a loss of triggers even though the –preserve-triggers option is specified. I made the decision to recreate the identical circumstance so that everyone could see it.
Test environment :
OS: Amazon Linux 2
MySQL version: 5.7.40
pt-online-schema-change version: 3.1.0
Before digging deeper, we must first obtain the whole picture.
Here is an illustration of the table’s structure.
Table structure:
…[Read more]
Rollback is an operation, which changes the current state of the transaction to the previous state. Undo logs are generally required if we want to roll back any of the uncommitted transactions and it plays a major role in Isolation.
For any changes made during a transaction, it must be stored priorly, because they are required if we choose to roll back the transaction.
Entries are made in undo logs when data modifications are done. If a transaction modifies data with SQL commands, It will create discrete undo logs for each operation. Once a transaction is committed MySQL is free to purge the undo logs created in that transaction.
To know more about undo logs, you can check our previous blogs on overview to undo logs.
Usually, the Rollback process will take more time than the original operation. Because …
[Read more]A year ago, I blogged about An Unprivileged User can crash your MySQL Server. At the time, I explained how to protect yourself against this problem. A few weeks ago, I revisited this vulnerability in a follow-up post in which I explained the fix, claimed that the MySQL 5.7 default configuration for Group Replication is still problematic, and explained a tuning to avoid the vulnerability. In
A year ago, I blogged about An Unprivileged User can Crash your MySQL Server. At the time, I presented how to protect yourself against this problem without explaining how to generate a crash. In this post, I am revisiting this vulnerability, not giving the exploit yet, but presenting the fix. Also, because the default configuration of Group Replication in 5.7 is still vulnerable (it is not in
Aurora has a salient feature “Parallel query“, Which will be more beneficial for analytical workload environments.
Before going to deep dive on this particular feature, let us understand the basis of Aurora.
Aurora Archiecture
- The key feature of Aurora is simple data synchronisation among the nodes. The sync latency will be too low when compared to RDS because the synchronisation is happening on storage volumes among the nodes. Also all the server will available in different zone, even when a zone goes down we can able to maintain will other server present in other zone with auto failure.
- Auto healing volume, Each …
From MySQL 5.7, we had a Multi-threaded Slave (MTS) Applier
mechanism called
LOGICAL_CLOCK
to overcome the
problems of parallel replication within a database.
To further improve the parallelisation mechanism, from MySQL 8 (5.7.22) we have write-set replication, so before going further , lets look at the difference between Logical clock (LC) and Writeset.
LOGICAL_CLOCK
Transactions that are part of the same binary log group commit on a master are applied in parallel on a slave. The dependencies between transactions are tracked based on their timestamps to provide additional parallelisation where possible.
WRITESET
Write-set
is a mechanism to track independent
transactions that can be executed in parallel in the slave.
Parallelising on write sets has potentially much more parallelism
than logical_clock
,since it does not depend …
MySQL configuration variables are a set of server system variables used to configure the operation and behavior of the server. In this blog post, we will explain the differences in managing the configuration variables between MySQL 5.7 and MySQL 8.0. We will explain three different ways for setting the configuration variables based on your use-case. […]