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MySQL, Percona, MariaDB long running processes clean up one liner

There are tools like pt-kill from the percona tool kit that may print/kill the long running transactions at MariaDB, MySQL or at Percona data instances, but a lot of backup scripts are just some simple bash lines.
So checking for long running transactions before the backup to be executed seems to be a step that is missed a lot.

Here is one line that might be just added in every bash script before the backup to be executed
Variant 1. Just log all the processlist entries and calculate which ones were running longer than TIMELIMIT:

$ export TIMELIMIT=70 && echo "$(date) : check for long runnig queries start:" >> /tmp/processlist.list.to.kill && mysql -BN -e 'show processlist;' | tee -a /tmp/processlist.list.to.kill | awk -vlongtime=${TIMELIMIT} '($6>longtime){print "kill "$1";"}' | tee -a /tmp/processlist.list.to.kill

Variant 2: Log all the processlist, calculate the calculate which processes are …

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Optimizer hints in MySQL 5.7.7 – The missed manual

In version MySQL 5.7.7 Oracle presented a new promising feature: optimizer hints. However it did not publish any documentation about the hints. The only note which I found in the user manual about the hints is:

  • It is now possible to provide hints to the optimizer by including /*+ ... */ comments following the SELECT, INSERT, REPLACE, …
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OurSQL Episode 207: Looking Forward

Podcasts Learning

In this penultimate episode, we talk about what's coming in MySQL 5.7 and MariaDB 10.1. Ear Candy is about a new MySQL 5.7 utility to generate the SSL RSA keys to encrypt MySQL communications, and At the Movies is about MySQL's new features.

OurSQL Episode 207: Looking Forward

Podcasts Learning

In this penultimate episode, we talk about what's coming in MySQL 5.7 and MariaDB 10.1. Ear Candy is about a new MySQL 5.7 utility to generate the SSL RSA keys to encrypt MySQL communications, and At the Movies is about MySQL's new features.

SSL/TLS in 5.6 and 5.5 – oCERT Advisory

Today, oCERT published advisory 2015-003 describing a TLS vulnerability in MySQL and derivative products.  The content isn’t exactly news – it is documented legacy behavior and the subject of an earlier blog post describing how MySQL Server 5.7 solves the problem.  That said, the efforts of Duo Security are certainly appreciated and welcomed – it provides a meaningful context to discuss how to properly harden existing MySQL 5.5 and 5.6 deployments, as well as frame a discussion on potential changes in these versions to increase security.

Vulnerability

The vulnerability described in the advisory relies on the legacy behavior of the client …

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Introducing the Power of Notifications

Since VividCortex launched its database monitoring platform, many users have requested some type of notification system. To address this, we took particular care in building a feature that proactively warns users of potential problems without sending multiple false alerts.

We are excited to announce notifications via email, PagerDuty and VictorOps. This post addresses basic functionalities, but please explore the feature and provide feedback to support@vividcortex.com.

What triggers a notification? Our events dashboard records behaviors such as high swap activity, disc faults, replication stopping, mysql server restarts and more. These events are grouped into incidents based on host and type. Depending on your systems, one or more of these may signal that you need to investigate further.

Do I have control over notifications? Of course. The last thing we want is an endless flow of useless …

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Percona Acquires Tokutek : My Thoughts #2 : TokuMX and TokuMXse

A few days ago I wrote up my thoughts about the Percona acquisition of Tokutek with respect to TokuDB. In this blog I'm going to do the same for TokuMX and TokuMXse. And in a few days I'll wrap up this trilogy by sharing my thoughts about Fractal Tree Indexes.

Again, when I'm writing up something that I was very involved with in the past I think it's important to disclose that I worked at Tokutek for 3.5 years (08/2011 - 01/2015) as VP/Engineering and I do not have any equity in Tokutek or Percona.

Since much of the MySQL crowd might be hearing about Tokutek's "other products" for the first time I'll provide a little history of both of the products before I dive in deeper.

TokuMX is a fork of MongoDB …

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Generated (Virtual) Columns in MySQL 5.7 (labs)

About 2 weeks ago Oracle published the MySQL 5.7.7-labs-json version which includes a very interesting feature called “Generated columns” (also know as Virtual or Computed columns). MariaDB has a similar feature as well: Virtual (Computed) Columns.

The idea is very simple: if we store a column

`FlightDate` date

in our table we may want to filter or group by year(FlightDate), month(FlightDate) or even dayofweek(FlightDate). The “brute-force” approach: use the above Date and Time MySQL functions in the query; however it will prevent MySQL from using an index (see below). Generated columns will allow you to declare a “Virtual”, non-stored column …

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Feedback directed optimization with GCC and Perf


Gcc 5.0 has added support for FDO which uses perf to generate profile. There is documentation for this in gcc manual, to quote:

-fauto-profile=path
Enable sampling-based feedback-directed optimizations, and the following optimizations which are generally profitable only with profile feedback available: -fbranch-probabilities, -fvpt, -funroll-loops, -fpeel-loops, -ftracer, -ftree-vectorize,
-finline-functions, -fipa-cp, -fipa-cp-clone, -fpredictive-commoning, -funswitch-loops, -fgcse-after-reload, and -ftree-loop-distribute-patterns.
path is the name of a file containing AutoFDO profile information. If omitted, it defaults to fbdata.afdo in the current directory.
Producing an AutoFDO …

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Netbeans 8 – Fedora

Some of my students want to use the Fedora image that I built for my database classes in my Java software development life cycle course. As a result, they wanted a Java development environment installed. I examined JDeveloper 11g (11.1.1.7.0) and 12c (12.1.3) but resolved on the more generic Netbeans 8 (8.0.2) IDE.

JDK 7 with Netbeans 8 Download

You can download the generic Netbeans 8 IDE, the JDK 7 with Netbeans, or the JDK 8 with Netbeans for the Linux installation. After you download the executable program, you should follow these instructions to install the Netbeans 8 IDE on Fedora.

As the …

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