Last time I shared a video that is an introduction to Using MySQL without the SQL. This
time I am adding two more videos -- one on Document Collections and another on simple indexes. The MySQL Document Store
is a simple, easy to use way to for developers to store data
without much of the traditional pre-requisite chores needed with
a relational database.
You simple connect to the MySQL instance using the new MySQL Shell to the schema of your choice,
create a document collection, and can start saving data right …
Percona XtraDB Cluster 8.0 is on the final stretch before GA release, and we have pre-release packages available for testing.
I wanted to see how Percona XtraDB Cluster 8.0 performs in CPU and IO-bound scenarios, like in my previous posts about MySQL Group Replication.
In this blog, I want to evaluate Percona XtraDB Cluster 8.0 scaling capabilities in cases when we increase the number of nodes and increase user connections. The version I used is available here: Percona-XtraDB-Cluster-8.0.18. …
[Read more]When I run a benchmark and want to measure the CPU efficiency of something, I find it’s often a good choice to run a benchmark program, as well as the database, on the same server. This is in order to eliminate network impact and to look at single-thread performance, to eliminate contention.
Usually, this approach gives rather stable results; for example, benchmarking MySQL with Sysbench OLTP Read-Only workload I get a variance of less than one percent between 1-minute runs.
In this case, though, I was seeing some 20 percent difference between the runs, which looked pretty random and would not go away even with longer 10-minute runs.
The benchmark I did was benchmarking MySQL through ProxySQL (all running on the same machine):
Sysbench -> ProxySQL -> MySQL
As I thought more about possible reasons, I thought CPU scheduling might be a problem. As requests pass …
[Read more]When connecting to a local MySQL instance, you have two commonly used methods: use TCP/IP protocol to connect to local address – “localhost” or 127.0.0.1 – or use Unix Domain Socket.
If you have a choice (if your application supports both methods), use Unix Domain Socket as this is both more secure and more efficient.
How much more efficient, though? I have not looked at this topic in years, so let’s see how a modern MySQL version does on relatively modern hardware and modern Linux.
Benchmarking TCP/IP Connection vs Unix Domain Socket for MySQL
I’m testing Percona Server for MySQL 8.0.19 running on Ubuntu 18.04 on a Dual Socket 28 Core/56 Threads Server. (Though I have validated results on 4 …
[Read more]Early on in the MySQL 8.0 Release series there were a couple of key items related to our everyday use. They are MySQL-Shell‘s establishing the “Pluggable Password Store” in 8.0.12, and its super enhance API Command Line Interface in 8.0.13… which the Pluggable Password Store also adopted. Sadly, most content highlighting the API CLI capability when it came… Read More »
It’s the in-between term time and we’re all stuck at home. I decided to update the image for my Fedora 30 virtual machine. I had a work around to the update issue that I had encountered last October in Bug #96969 but it was not required with the current version. However, after updating from MySQL 8.0.17 to MySQL 8.0.19, I found that my Java connection example failed.
The $CLASSPATH value was correct:
/usr/share/java/mysql-connector-java.jar:.
The first error that I got was the my reference to MySQL JDBC driver was incorrect. The error message is quite clear:
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary. Cannot connect to database server: The server time zone …[Read more]
In this post, I want to evaluate Group Replication Scaling capabilities in cases when we increase the number of nodes and increase user connections. While this setup is identical to that in my post “Evaluating Group Replication Scaling Capabilities in MySQL”, in this case, I will use an I/O bound workload.
For this test, I will deploy multi-node bare metal servers, where each node and client are dedicated to an individual server and connected between themselves by a 10Gb network.
Also, I will use 3-nodes and 5-nodes Group Replication setup. In both cases, the load is directed only to ONE node, but I expect with five nodes there is some additional overhead from replication.
Hardware specifications:
System | Supermicro; SYS-F619P2-RTN; v0123456789 (Other) Service Tag | …[Read more]
Recently, we were affected by an ignored configuration option introduced in MySQL 5.6. This incident caused us to perform extended planning of downtime and the rebuilding of the slave. In…
The post Still have MySQL 5.6 variable binlog_error_action as IGNORE_ERROR? first appeared on Change Is Inevitable.
The backup and restore of a complete database is an extensive exercise. But what if you need to restore just one table which has been mistakenly modified by an incorrect query? Help is at hand with Percona XtraBackup.
For our purpose, we will take a test database having tables created by the sysbench tool. The 8.0 versions of Percona XtraBackup and Percona Server for MySQL have been used in this test.
Restore Single Table
Here we will take the backup of the sbtest2 table and restore it. The initial checksum of the table is given below:
8.0.19>CHECKSUM TABLE sbtest2; +--------------+-----------+ | Table | Checksum | …[Read more]
This is our third ‘multi-master MySQL’ blog in our Continuent MySQL Use Case series, with a focus on Telco providers. This blog concludes our multi-master MySQL mini-series along with the following two blogs:
- Multi-master MySQL for e-Commerce Sites
- Geo-distributed Multi-master MySQL for Financial Services SaaS Providers
As per our initial multi-master MySQL use case blog, multi-master replication for MySQL typically means that a user can write to any master node knowing that the write will be eventually consistent for …
[Read more]