The following report is covering performance evaluation of the currently available OpenSSL releases when they are used by MySQL in CPU-intensive OLTP workloads. However, the main focus is on OpenSSL-3.5.5, which will be used by default in the next MySQL releases.
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Having a separate DR cluster for production databases is a modern day requirement or necessity for tech and other related businesses that rely heavily on their database systems. Setting up such a [DC -> DR] topology for Percona XtraDB Cluster (PXC), which is a virtually- synchronous cluster, can be a bit challenging in a complex Kubernetes environment.
Here, Percona Operator for MySQL comes in handy, with a minimal number of steps to configure such a topology, which ensures a remote side backup or a disaster recovery solution.
So without taking much time, let’s see how the overall setup and configurations look from a practical standpoint.
PXC Cross-Site/Disaster Recovery
DC Configuration
1) Here we have a three-node PXC cluster running on the DC side.
shell> kubectl get pods -n pxc NAME READY STATUS …[Read more]
You read this right, symbolic links (symlinks) are unsafe in MySQL since at least 8.0.39. As always, it is a little more complicated than that, but if you are using symbolic links and in certain conditions, you risk a crash. I think it is important to raise awareness on this, hence this post.
My attention was brought to this via the now private Bug #120156: MySQL 8.0.39/8.0.42
I am continuing my blog post series on using indexes — or tables — as queues. In this post, I cover Row Deletion Jobs (I do not call these purge jobs, to avoid confusion with the InnoDB Purge). Such jobs are tempting to implement using an index, but this might be a wrong / suboptimal way. I write about the right / better / cheaper way
I am starting a blog post series on using indexes — or tables — as queues. I had this series in the back of my mind for some time. This started a few years back when I worked on optimizing a row deletion job (I do not call this a purge job, to avoid confusion with the InnoDB Purge). Such jobs can be generalized to using indexes (or tables) as queues (this is
Something changed in MySQL 8.4 related to caching, and it is easy to miss, so it deserves a post. And a subject adjacent to this is the missing Release Candidate for MySQL 8.4 LTS, with my hope that the next LTS will have a Release Candidate, so I also cover this topic below.
(if you are not interested in Caching and Flushing, you can jump directly to the section about Release Candidate)
I am upset about this one : I have a hard time not seeing this as negligence, and it starts to become a pattern... So please forgive me if this post is not my most diplomatic, because I really think someone deserves a kick in the butt ! But what is all this about...
There is a MySQL bug, which can lead to data corruption, opened for 8.0 in September 2023, fixed in MySQL 8.4.0 (
A unique constraint specifies, one or more columns as unique it identifies. It is satisfied only when no two rows store the same non-null values at its core. A primary key constraint is a unique one that will say PRIMARY KEY in its defined way. It is satisfied only when rows unfold, and none may […]
In a recent post, The Quirks of Index Maintenance in Open Source Databases, I compared the IO load generated by open source databases while inserting rows in a table with many secondary indexes. Because of its change buffer, InnoDB was the most efficient solution. However, that’s not the end of the story. Evolution of the […]
When you run a simple write, …it may look simple, but under the hood, MySQL’s InnoDB engine kicks off a pretty complex sequence to ensure your data stays safe, consistent, and crash-recoverable. In the top-left corner of the diagram, we see exactly where this begins — the moment the query is executed: [crayon-697773637c60c399076158/] The log […]