This is the very first post in the series of Performance Schema Implementation Internals. This series is for MySQL Developers to understand implementation of Performance Schema. For user point of view of performance Schema, please refer to mysql documentation link : http://dev.mysql.com/doc/refman/5.7/en/performance-schema-quick-start.html

This post talks about the mechanism to register instruments in Performance Schema (referred as P_S from hereon) so that their …

Most technologies achieving high-availability for MySQL need a load-balancer to spread the client connections to a valid database host, even the Tungsten special connector can be seen as a sophisticated load-balancer. People often use hardware load balancer or software solution like haproxy. In both cases, in order to avoid having a single point of failure, multiple load balancers must be used. Load balancers have two drawbacks: they increase network latency and/or they add a validation check load on the database servers. The increased network latency is obvious in the case of standalone load balancers where you must first connect to the load balancer which then completes the request by connecting to one of the database servers. Some workloads like reporting/adhoc queries are not affected by a small increase of latency but other workloads like oltp processing and real-time logging are. Each load balancers must also check regularly if the database …

As we know, one of the most important config for InnoDB is the innodb_buffer_pool_size, it basically store the innodb data and indexes in memory, when MySQL receives a query and the InnoDB pages involved on that query are stored in the buffer, it does not need to go to the disk to return the result, which is much faster (memory speed vs disk speed).

As it is stored in memory, every time you restart your MySQL server it starts with a clean/empty buffer pool and usually it take some time to warm-up the buffer.
To speed up this process, we can configure 2 variables that will dump and reload the pages reference stored in the buffer, this is a new functionality added on MySQL 5.6 (it was presented on previous versions of Percona Server and MariaDB).

If you have your production server already running, we are going to set it to dump the content every time it shutdown:

SET GLOBAL innodb_buffer_pool_dump_at_shutdown = 1; …

We are pleased to announce that MySQL Enterprise Monitor 2.3.15 is now available for download on the My Oracle Support (MOS) web site. This is a maintenance release that fixes a number of bugs. You can find more information on the contents of this release in the change log.

You will find binaries for the new release on My Oracle Support. Choose the "Patches & Updates" tab, and then choose the "Product or Family (Advanced Search)" side tab in the "Patch Search" portlet.

As an alternative to upgrading to MySQL Enterprise Monitor (MEM) 2.3.15, we highly recommend that you consider MEM 3.0. Based on feedback from our customers, MEM 3.0 offers many significant improvements over MEM 2.3. Highlights include:

• Policy-based automatic scheduling of rules and event handling …

We recognize that the most important part to get you started is getting the products you want installed and well configured. That's why the installer team has been working really hard to enhance the user experience with MySQL products. We are proud to announce a newer, lighter version of the MySQL Installer is available for download at our website.

Have you tried the new MySQL Web Installer yet? Do it now!

It weights barely more than 1.5 MB in total but packs the ability to let you select any product from the MySQL family. The web installer will  handle the process of downloading, and installing what you need and will help you with configuration too.

This is part of the ongoing work on improving the transaction life cycle management. In 5.7.2 we split the transaction list into two. The read-only transaction list and the read-write transaction list. There was another “virtual” list, the auto-commit non-locking read-only (AC-NL-RO) transaction list. The change in 5.7.2 was that by default a transaction was treated as read only and added to the read-only transaction list. Only when it was determined that the transaction was going to do an update we removed the transaction from the read-only list and moved it to the read-write transaction list. This initial add to the the read-only list forced the acquisition of the trx_sys_t::mutex. Acquiring the mutex during transaction start/begin has a cost. Promoting a transaction from read-only to read-write we had to acquire the trx_sys_t::mutex to add to the read-write transaction list and so that is not too expensive and is unavoidable. There is another …

One of our primary focuses at Percona is performance. Let me make some statements on what is “performance.”

In doing so I will refer to two pieces of content:

• Carry Millsap’s talk “Performance Instrumentation: Beyond What You Do Now” [1]
• White Paper (by Peter and Baron) “Goal-Driven Performance Optimization” [2]

I highly recommend that you familiarize yourself with both of them.

Performance

Performance is about tasks and time.
We say that the system is performing well if it executes a task in an acceptable period of time, or that the …

I was busy testing a PXC cluster today when suddenly was buffled with a confusing error:

140108 23:33:39 innobackupex: Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup' (using password: NO).
innobackupex: Error: Failed to connect to MySQL server as DBD::mysql module is not installed at /usr/bin/innobackupex line 2913.

OK, so my first though was DBD::mysql is missing, but as I checked:

[root@pxc03 keepalived]# yum list installed| grep perl-DBD-MySQL
perl-DBD-MySQL.x86_64 4.013-3.el6 @base

After some digging, it’s not actually the module that is missing – it was one of the module’s dependency which is the mysql client library.

[root@pxc03 keepalived]# yum deplist perl-DBD-MySQL.x86_64|grep mysql
dependency: libmysqlclient.so.16()(64bit)
provider: mysql-libs.x86_64 5.1.71-1.el6
dependency: libmysqlclient.so.16(libmysqlclient_16)(64bit)
provider: mysql-libs.x86_64 …

High-Velocity Data—AKA Fast Data or Streaming Data—seems to be all the rage these days. With the increased adoption of Big Data tools, people have recognized the value contained in this data and they are looking to get that value in real-time instead of a time-shifted batch process that can often introduce a 6-hour (or more) delay in time-to-value.

High-velocity data has all of the earmarks of a big technological wave. The technology leaders are building stream processors. Venture firms are investing money in stream processing companies. And existing tech companies are jumping on the bandwagon and associating their products with this hot trend; making them buzzword compliant.

Some have asked whether high-velocity data will complement or replace Big Data. Big Data addresses pooled data, or data at rest. History tells us that there are …

High-Velocity Data—AKA Fast Data or Streaming Data—seems to be all the rage these days. With the increased adoption of Big Data tools, people have recognized the value contained in this data and they are looking to get that value in real-time instead of a time-shifted batch process that can often introduce a 6-hour (or more) delay in time-to-value.

High-velocity data has all of the earmarks of a big technological wave. The technology leaders are building stream processors. Venture firms are investing money in stream processing companies. And existing tech companies are jumping on the bandwagon and associating their products with this hot trend; making them buzzword compliant.

Some have asked whether high-velocity data will complement or replace Big Data. Big Data addresses pooled data, or data at rest. History tells us that there are different use cases and …