This blog compares how PostgreSQL and MySQL handle millions of queries per second.

Anastasia: Can open source databases cope with millions of queries per second? Many open source advocates would answer “yes.” However, assertions aren’t enough for well-grounded proof. That’s why in this blog post, we share the benchmark testing results from Alexander Korotkov (CEO of Development, Postgres Professional) and Sveta Smirnova (Principal Technical Services Engineer, Percona). The comparative research of PostgreSQL 9.6 and MySQL 5.7 performance will be especially valuable for environments with multiple databases.

The idea behind this research is to provide an honest comparison for the two popular RDBMSs. Sveta and Alexander wanted to test the most recent versions of both MySQL and PostgreSQL with the same tool, under the same challenging …

In this blog post, we’ll find out how to use Percona XtraBackup on a MySQL instance with a large number of tables.

As of Percona Xtrabackup 2.4.5, you are required to have enough open files to open every single InnoDB tablespace in the instance you’re trying to back up. So if you’re running innodb_file_per_table=1, and have a large number of tables, you’re very likely to see Percona XtraBackup fail with the following error message:

InnoDB: Operating system error number 24 in a file operation.
InnoDB: Error number 24 means 'Too many open files'
InnoDB: Some operating system error numbers are described at http://dev.mysql.com/doc/refman/5.7/en/operating-system-error-codes.html
InnoDB: File ./sbtest/sbtest132841.ibd: 'open' returned OS error 124. Cannot continue operation
InnoDB: Cannot …

I’ve been lately compiling and generating .deb packages for several MySQL and MariaDB recent versions, and I wanted to try them more in depth -specially MySQL 8.0 and MariaDB 10.2, both of which are still in development.

Several people have already given their first impressions (or will do soon), and testing early is the best way to catch bugs and regressions, and get them fixed before the official release. In fact, as I will comment later, I ran into breaking bugs on both MySQL 8.0 and MariaDB 10.2, which I …

This blog post discusses how better MySQL 8.0 benchmarks can improve MySQL in general.

Like many in MySQL community, I’m very excited about what MySQL 8.0 offers. There are a lot of great features and architecture improvements. Also like many in the MySQL community, I would like to see MySQL 8.0 perform better. Better performance is what we always want (and expect) from new database software releases.

Rarely do performance improvements happen by accident – they require running benchmarks, finding bottlenecks and eliminating them. This is the area where I think things could use improvement.

If you come to the MySQL Keynote at Oracle OpenWorld, or if you go to MySQL …

In this blog post, I’ll discuss how to use the InnoDB buffer pool pre-load feature in MySQL 5.7

Starting MySQL 5.6, you can configure MySQL to save the contents of your InnoDB buffer pool and load it on startup. Starting in MySQL 5.7, this is the default behavior. Without any special effort, MySQL saves and restores a portion of buffer pool in the default configuration. We made a similar feature available in Percona Server 5.5 – so the concept has been around for quite a while.

Frankly, time has reduced the need for this feature. Five years ago, we would typically store databases on spinning disks. These disks often took quite a long time to warm up with normal database workloads, which could lead to …

Percona announces the release of Percona Server 5.5.53-38.4 on November 18, 2016. Based on MySQL 5.5.53, including all the bug fixes in it, Percona Server 5.5.53-38.4 is now the current stable release in the 5.5 series.

Percona Server is open-source and free. You can find release details in the 5.5.53-38.4 milestone on Launchpad. Downloads are available here and from the Percona Software Repositories.

Removed Features:

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In this blog, we’ll discuss changing the tablespace directory using pt-online-schema-change.

One of the most annoying situations in the life of a DBA is realizing that the disk where the datadir resides is running out of space. If you’re lucky enough to run over an LVM volume or a RAID (depending on the level, though), it is easy to add disk space. But what if you are not that lucky, and your datadir is running on a single disk? Not so funny!

That is the exact situation we recently faced with a customer, for both the master and slave server. When trying to figure out a solution we saw that:

• There was enough space on a different partition within the same server.
• The tables have their own tablespace (innodb_file_per_table = on)
• The MySQL version was …

My recent post about importing a big dataset from InnoDB into MyRocks has attracted quite a lot of attention (thank you Mark!) and also it has been pointed out that what I wrote about coexistence of MyRocks and InnoDB was incorrect.

In fact, I had been asking about it at Percona Live last month, but got a negative answer.... plus I had tried it at first but got a mysqld crash during crash recovery once, so since it was not important for my use case I went ahead and disabled InnoDB entirely.

But of course, as I have written previously, using both engines in the same server is something that I would really, really love to have, so I thought to give it a try with a very simple use case.

So I created the following two tables, each one with a different engine:

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MySQL-Sandbox installs the MySQL server in isolation, by rejecting existing option files using the option --no-defaults. This is usually a good thing, because you don't want the initialization to be influenced by options in your /etc/my.cnf or other options files in default positions.

However, such isolation is also a problem when you need to add options during the initialization. One example is innodb-page-size, which can be set to many values, but only if the server was initialized accordingly. Thus, you can't set innodb-page-size=64K in your configuration file because the default value is different. It would fail, as InnoDB would conflict.

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This blog post discusses an information script for the Percona Monitoring and Management (PMM) tool.

In recent news, we announced the fresh-of-the-press Percona Monitoring and Management (or PMM for short) platform. Given the interaction of the different components that together make up PMM, I developed a script that helps provide you information about the status of your PMM installation.

You can use this script yourself, or one of our support might point you to this page to obtain the information they need to troubleshoot an issue you are experiencing.

You will likely want to execute this script once on the PMM …